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Topic: Evolution in action? (Read 38766 times)
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jucce
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I don't agree. A quote from Darwin himself: http://en.wikipedia.org/wiki/Punctuated_equilibrium
the periods during which species have undergone modification, though long as measured in years, have probably been short in comparison with the periods during which they retain the same form. (1869:551) http://en.wikipedia.org/wiki/Punctuated_equilibrium
Critics of punctuated equilibrium, such as Richard Dawkins, have argued that the concept of phyletic gradualism was merely a straw man—arguing that a belief in the uniformity of rates was never really held by any serious evolutionist (Dawkins 1986, 223-224, 228).
The actual differences between the various evolutionary theorists were not as large as they were made to appear (Dawkins 1986, 236). Gould himself later said that the theory did not in fact refute Darwin's gradualism, but just added the ideas of catastrophism and stasis. In much of the criticism seems to be simply that punctuated equilibrium shouldn't be separated from the evolution theory, it's already a part of it: http://en.wikipedia.org/wiki/Punctuated_equilibrium
What needs to be said now, loud and clear, is the truth: that the theory of punctuated equilibrium lies firmly within the neo-Darwinian synthesis. It always did. It will take time to undo the damage wrought by the overblown rhetoric, but it will be undone. (Dawkins 1986) http://en.wikipedia.org/wiki/Punctuated_equilibrium
Punctuated equilibrium is therefore mistakenly thought to oppose the concept of gradualism, when it is actually more appropriately understood as a form of gradualism (in the strict and literal sense of biological continuity).(Eldredge and Gould 1972) The point is that the change is still gradual. It's just that there may be periods were a species changes relatively little and then periods in which it changes more.
http://en.wikipedia.org/wiki/Phyletic_gradualism
Phyletic gradualism has been largely deprecated as the exclusive pattern of evolution by modern evolutionary biologists in favor of the acceptation of occurrence of patterns such as those described on punctuated equilibrium, quantum evolution, and punctuated gradualism. http://www.talkorigins.org/faqs/punc-eq.html
PE is not mutually exclusive of phyletic gradualism. Gould and Eldredge take pains to explicitly point out that PE is an expansive theory, not an exclusive one (1977).
I don't think we'd see that clearly delimited species, the change is more gradual. Now isn't this the issue between gradualism and punctuated equilibrium?
Like I wrote above, they are not at odds with each other.
Well fossils do take some special circumstances to form and who knows how many fossils are left out there. But what's interesting is that we're constantly finding new fossils that appear to be "missing links". I just did a search on Google news quickly: That's just it, we are NOT constantly finding new fossils that appear to be missing links. We are finding many more animals that do not fit into the tree of life and completely different phyla.
The scientists who found the fossils are openly stating that they look like missing links. I don't see the fact that we are finding new animals that doesn't fit in a specific position as a problem.
This is a completely new insect and just because it's genome is more consistent with the praying mantis than a cockroach is irrelevant. The two genomes of any given frog species can have many times the difference between the genome of a bat and a blue whale. They had more to go on that just its genome, it's in the article.
So because my TV has a circuit board and my car has a circuit board one evolved from the other?
No. I don't see how that's relevant.Modern mammals have an inner ear separated from their lower jaw that allows them to better hear air-borne sounds. Reptiles have an inner ear attached to their jaw to better sense vibrations on the ground.
Yanoconodon's inner ear, however, is in the back of the jaw, connected by cartilage.
"What this amazing skeleton from China shows," Beard said, "is an intermediate step -- like a missing link in an evolutionary series -- from a lizard condition to a mammal condition."
Could be? Why EXACTLY is it a missing link? Because it's old? Because it fits the same phyla? Because of the FACT of evolution and that cuttlefish, squids and octopus had to evolve from a common ancestor?
It looks like a missing link for several reasons, but it's a relatively new find. Here's some information at least: http://scienceblogs.com/pharyngula/2007/03/orthozanclus.php
If educated people working in that field sees a specific feature that only exists within a certain group then I'd say the animal also belongs to that group. From what I understand they've also done genetic testing. It seems it evolved from some sort of hippopotamus and evolved to the (air-breathing) dolphin. The Ambulocetus natans is also from the same suborder. http://en.wikipedia.org/wiki/Evolution_of_cetaceans#Pakicetids:_the_earliest_cetaceans.3FThe shape of the ear region in Pakicetus is highly unusual and only resembles the skulls of whales. The feature is diagnostic for cetaceans and is found in no other species. According to Thewissen, the teeth of Pakicetus also resemble the teeth of fossil whales, which is another link to more modern whales.[ 3] Dude they determined it was a ancestor to modern dolphins based on a skull and similarties in the inner ear. They determined that Tiktaalik was a walking mammal when the only remains they had was a skull, nothing more. they haven't found a complete skeleton. How do we know it wasn't an ancient whale/dolphin species?
Are you referring to the Tiktaalik with the lack of a complete skeleton? As I understand it they have nearly complete fossils of that. And when it comes to the Pakicetus, I don't see your problem. They examined the skull, found strong similarities between the teeth and the inner ear of other ceteceans. In fact only cetaceans have those same inner ear features.
The wikipedia page on Tiktaalik is interesting, scientists do study these fossils and work to determine where they fit/what they are. http://en.wikipedia.org/wiki/Tiktaalik
That's true, it may not be a proper missing link. But there are 46 others on that list and like I said, it seems like we just keep finding new ones. And also the Archaeopteryx which you agreed is a very plausible missing link. Most of the 46 others are superficial bone differences not outside the realm of limited, microevolution. And even though Archaeopteryx is a plausible missing link, doesn't mean it is one. The Duckbilled platupus is among a very few species of egg laying mammals yet nobody is casting these living animals as missing links between reptiles or birds to mammals.
No I don't agree that you can disregard all those probable transitional fossils with "superficial bone differences not outside the realm of limited, microevolution". Also, like I said, during the last years we've just been finding more and more of these. Of course when it comes to the Archaeopteryx for example we will probably never be 100% sure of a specific find, but the sum of the evidence does point in one direction.
There is solid research on this subject: http://www.palaeos.com/Vertebrates/Units/140Sarcopterygii/140.000.html http://vuletic.com/hume/cefec/5-1.html http://vuletic.com/hume/cefec/5-2.html http://vuletic.com/hume/cefec/5-3.html http://vuletic.com/hume/cefec/5-4.html http://vuletic.com/hume/cefec/5-5.html http://vuletic.com/hume/cefec/5-6.html and obviously much much more.
And of course they don't claim that Platypuses are missing links to bird or reptiles. There is solid science behind all of this, not guesswork: http://en.wikipedia.org/wiki/Platypus#In_mammalian_evolution
Yes but that theory "punctuated equilibrium" seems to coroborate that. There is much stasis and then quick bursts of evolution, kind of "the last drop". When it happens it happens alot in a short time, like a dam breaking. Also if one species evolves a specific benefit it may cause a sort of "arms race" because the pressure on other species will increase rapidly. So evolution may also fuel itself. As stated before, PE is fraught with it's own problems and is not a widely accepted paradigm.
Like I said before, I don't agree with that.
That isn't the entire eye but what takes place inside a single human photoreceptor cell. Since you argue that the human eye is built from "simple" to more complex I thought I'd show just how "simple" a single photo receptor cell is. We see precision and purpose from the most minute microscopic detial of our modern eye to the largest features such as eyelids, control muscles, tear ducts etc.
The eye is not perfect, take the blind spot for example. And it's no surprise that the attributes surrounding our eye have a use, that's why they were passed on to the next generation. Furthermore things like eyelids most likely came early in animal (eye) developement.
I don't know how primitive a cell could be to only be able to detect light. But photons do impact and affect cells creating some kind of reaction. It's not just "some kind of reaction" but a highly prefected interaction of specific and complex protiens and enzymes. We see specific functions at every level of complexity conspiring to achieve vision regardless of how "simple" the eye itself is.
Like I said, I don't know exactly how simply a cell would have to be to be able to register light and I doubt you do either. It would definitely be less complicated than the cells in our eyes. In fact there are animals today who have very simple photo-sensitive cells, just simple enough to detect light.
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« Last Edit: March 26, 2007, 03:24:21 am by jucce »
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jucce
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Also photosynthesis is strongly connected to light and light sensitivity. Just think about algae and some bacteria. Oranges and apples. Photosyhthesis is a process by which plants and algea turn sunlight into useable energy. "light sensetivity" as you marginalize this complex and specifc function we call sight, has nothing to do with photosynthesis and turns photonic information into electirical signals to be interpreted by the brain.
That proves there was light sensitive chemistry around. If photosynthesis could arise then surely light sensitivity in cells could. And the reason I simplify it as light sensitivity is because there was a gradual evolution from there.
I mean what is photosynthesis? A conversion of light to chemical energy. In fact some plants move towards the sun, that's hardly a long step from simple sea-living animals moving towards the sun. http://en.wikipedia.org/wiki/Heliotropism In fact there is animal heliotropism too.
For example here is a single cell organism that's evolved an eyespot to find the best location for photosynthesis: http://ebiomedia.com/gall/eyes/primitive.html
That whole link is a just-so story built around darwinian dogma. I especially liked this: "And, according to one scientist's calculations, only 364,000 years would have been needed for a camera-like eye to evolve from a light-sensitive patch. "I'd like to see this guy's calculations... How do you come to the conclusion that this is "darwinian dogma"? This guy wanted a PhD on insect eyes and has one on crustacean eye optics, he's also a professor in zoology. And he's also written books on mathematics. It seems like you have to pay for his paper, but here's his homepage: http://www.biol.lu.se/funkmorf/vision/dan/Dan.html
Once again, interesting but conclusive? Only if you are a firm believer in the "fact" of evolution. It's fascinating that lizards see in two colors but can we really conclude much more than that ?
Which "we"? Certainly well educated scientists who work in that area seem to believe that this is significant.
" So cubozoan eyes are good for spotting large, stationary objects, while filtering out unnecessary detail such as plankton drifting with the current. So the jellyfish eyes are specialized to their environment. Specifed and purposeful. " From here it would be an easy step to evolve an image-forming eye." Well if it's any easy step then by all means demonstarte it in the lab!!! I love the darwinist's magic wand, happily skipping over volumes of complexity with the wave of a hand. The point is that they have an eye that has potential to be very accurate but the image is focused behind the retina. So the next step would be to further evolve this eye. So this looks like an intermediary stage in the evolution of the eye. Actually having this animal evolve in a lab in the direction of your choosing is not feasible.
Did you follow the link in that wiki article? http://news.nationalgeographic.com/news/2001/08/0822_starfisheyes.htmlScientists have discovered a species of brittle star whose outer skeleton is covered with crystalline lenses that appear to work collectively as an all-seeing eye. ... "These lenses have exceptional optical performance," said Aizenberg, who is co-author of a report on the discovery published in the August 23 issue of Nature. "They are compensated for physical effects that bother us when we fabricate lenses in the laboratory"—effects known as birefringence and spherical aberration. So how does this fit with the evolution from light sensetive cell to modern complex shutter camera eyes of humans? a light-sensitive patch will gradually turn into a focused lens eye through continuous small improvements of designShow me the emperically testable evidence please.
That's what I've been trying to do, linking to countless fossils, transitional eyes, rudimentary eyes, primitive eyes, degenerate eyes, scientific theories, mathematical models, computer simulations and so on. http://en.wikipedia.org/wiki/Evolution_of_the_eye
We can't simulate or recreate the entire evolution of Earth in a lab. So we have to use the scientific method and figure out a theory that fits reality.
Covered this earlier. The evolutionary computer program called ALife is a simple computer program designed to succeed and is not really a realistic example of evolution though random mutation and natural selection. Natural selection is not an absolute series of IF THEN statements that will weigh in favor of a given function every time. Further more, the AND, XOR , EQU etc. functions that the program rewards were written ahaed of time and represent easy to evolve 3 sequence of characters. Protien sequences are at leats 50 amino acids in length or larger and each amino acid sequence is written by 3 base pairs in the DNA structure.
It's not a complete simulation of the evolution of live on Earth but a model of evolution. From where did you get that it's created to succeed?. Also the program is more than just IF THEN statements:
The program, called Avida, is an artificial petri dish in which organisms not only reproduce, but also perform mathematical calculations to obtain rewards. Their reward is more computer time that they can use for making copies of themselves. Avida randomly adds mutations to the copies, thus spurring natural selection and evolution. The research team watched how these "bugs" adapted and evolved in different environments inside their artificial world. And it's not the only example. http://en.wikipedia.org/wiki/Artificial_life
"The idea is simply that you fiddle around and you change something and then you ask, Does it improve my survival or not? And if it doesn't, then those individuals die and that idea goes away. And if it does, then those individuals succeed, and you keep fiddling around, improving. It's an enormously powerful technique." It is indeed a powerful idea. But if you can "simply fiddle around" why does it reamin so elusive in the lab?
Didn't we just talk about things like nylonase? And genetically modified crops are big. Or what are you looking for? Stuff like this? http://www.talkorigins.org/faqs/faq-speciation.html http://www.talkorigins.org/faqs/speciation.html
I'll look at these later.. And I'm sure there's much more. But the idea is like with the eye, gradual evolution. In these links you provided I see references to gradualism but I have yet to read anything regarding expirimental science confirming such speculation. Thats all it is, speculation and just-so stories based around a centeral evolutionary idea. It's not speculation. I've given you sources to multiple examples of rudimentary eyes, transitional eyes, theories on the formation of eyes etc. Just because we can't be 100% sure of every detail on the developement of eyes doesn't mean the theory is all wrong and needs to be discarded.
Again theories like punctuated equilibrium agree with that. And fossil formation is a rare occurence. Punctuated Equilibrium is the opposite of gradualism so it doesn't "agree with that". As I said before, I don't agree.
Well they claim that Rhagoletis pomonella is becoming a separate species. Then there's the Nylonase. And what about the pig or the dog? So we can certainly get new species. There probably are problems with breeding a dolphin to the size of a blue whale for example, the physiology of the animal may not be compatible with such a big size. Human populations have lived in realitive isolation for thousands of years. Micro evolution is evident. Africans, Chinese and Europeans for example exhibit distinct characteristics. So according to this logic, if humans remained isolated they would eventually become a different species. Somthing I don't think will ever occur. This idea is a centeral theme to Darwin's gradualism but unfortunately has never been documented or reproduced in a lab in any capacity. Even bacteria which we can reproduce into the trillions upon trillions of generations and witness real time mutation by sequencing their genome never produce anything but the same species. It's a pipe dream man, I'm telling ya. Do you want examples of speciation (including in labs and due to isolation)? http://www.talkorigins.org/faqs/faq-speciation.html http://www.talkorigins.org/faqs/speciation.html http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/Speciation.html http://www.nd.edu/~aforbes/ http://www.pnas.org/cgi/content/full/96/13/7348
Once again, yeast cells produce nothing novel morphically and are just more yeast cells with some unique genetic characteristics. They even admit to microevolutionary changes.
They're saying that this is early in the process of speciation.
By repeating this selection process for 36 generations, the researchers produced evolved populations that were five times more likely to mate to other evolved cells than they were to the reference population.
Sigh.. Really? Two isolated "species" of frog creating a hybrid. So what, where's the evolution? If they can interbreed then they aren't a seperate species to begin with.
No, that's right, they weren't two different species to begin with.
This example suggests that rapid speciation is often driven by recontact between long-isolated populations, Moritz said. Random drift between isolated populations can produce small variations over millions of years, whereas recontact can amplify the difference over several thousands of years to generate a distinct species.
Sigh..Bipedabilty requires some sophisticated hardware, especially in the inner ear and the equilibrium of the species. Not only that, just because our hands were "freed up" doesn't mean we had the intelligence to use tools. This is one of those just-so stories that really isn't backed by anything other than believing the "fact" of evolution. I've given you multiple sources for this theory. Something as simple as picking up a rock and hitting a nut with it is using a basic tool. From there on our use of tools just accelerated. Many animals can stand on two legs well. And especially monkeys who really have great balance, you need that if you're living in trees.
.. that's all I have time for today.
btw. About goosebumps on humans. Think what happens to the human body while in cold water. Especially if you are a man. The body has an interesting way of conserving heat.
Just like with the nipples I ask, do the erector pili have anything to do with that?
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« Last Edit: March 26, 2007, 03:23:39 am by jucce »
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RTyp06
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The scientists who found the fossils are openly stating that they look like missing links. I don't see the fact that we are finding new animals that doesn't fit in a specific position as a problem. That's because stating so isn't heresy in modern biology where Darwinism is the reigning paradigm. In any other branch of science, making such flimsy claims without solid scientifc data would be frowned upon.
And nobody is saying there is a problem, just that the fossil record isn't providing the undeniable evidence predicted by Darwin.
They had more to go on that just its genome, it's in the article. Yes they did have more to go on than the Genome and the animal's "posture" which is measureable and demonstrateable real science... a firm belief in the "fact" of evolution.
No. I don't see how that's relevant. Modern mammals have an inner ear separated from their lower jaw that allows them to better hear air-borne sounds. Reptiles have an inner ear attached to their jaw to better sense vibrations on the ground.
Yanoconodon's inner ear, however, is in the back of the jaw, connected by cartilage. So what? This is evidence of different ears suited to the individual specie's enviornment. Extrapolating any further links comes soley from a firm belief in biological evolution and not any real world testable evidence.
And when it comes to the Pakicetus, I don't see your problem. They examined the skull, found strong similarities between the teeth and the inner ear of other ceteceans. In fact only cetaceans have those same inner ear features. They found a skull of an ancient whale.. That is it. So what?
No I don't agree that you can disregard all those probable transitional fossils with "superficial bone differences not outside the realm of limited, microevolution". Also, like I said, during the last years we've just been finding more and more of these. Of course when it comes to the Archaeopteryx for example we will probably never be 100% sure of a specific find, but the sum of the evidence does point in one direction.
How can you sum up a mere 46 fossils mostly made of bone fragments and come to any concrete conclusion? Think of the difference in skeletons of a grate dane, bulldog and a chiauaua alone..
Of course there isn't guesswork when you have a living, breathing example! What if they found a living Archaeopteryx ? Just like the Coelacanth, museums had all kinds of displays and scietists were convinced this animal represented evolution encarnate. When it was only known from the fossil record this was a slam dunk example of evolution.. That is until they found it living off the coast of Africa and quickly took down the exhibits and distanceed themseleves from this absolute embarassment!
The eye is not perfect, take the blind spot for example. And it's no surprise that the attributes surrounding our eye have a use, that's why they were passed on to the next generation. Furthermore things like eyelids most likely came early in animal (eye) developement. What about the blindspot? It doesn't hinder us in anyway and mammals are thought to have some of the best eyesight in the animal kingdom. And it's not a matter wether or not the attributes surrounding our eye have a use or not, it's how did they evolve in the first place? It's one thing to wave the magic evolutionary wand and say things like " and then the first fishes or amphibians walked out onto dry land", but think of the multitudes of complexity that need to be in place and working before this is even possible. Were talking a completely different enviornment here. Tear ducts and eyelids for example were crucial for this step. Not to mention legs able to support the animal, lungs to breathe etc. This would be about like humans evolving to walk on the lunar surface.
Like I said, I don't know exactly how simply a cell would have to be to be able to register light and I doubt you do either. It would definitely be less complicated than the cells in our eyes. In fact there are animals today who have very simple photo-sensitive cells, just simple enough to detect light. There is nothing simple about any living cell found anywhere at any time. There is no reason to suspect that the cells found inside say a trilobite are any less complicated than any cell found living today. The ONLY reason we would ever expect to find simpler versions of cells is in light of evolutionary theory.
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RTyp06
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That proves there was light sensitive chemistry around. If photosynthesis could arise then surely light sensitivity in cells could. And the reason I simplify it as light sensitivity is because there was a gradual evolution from there. We are still talking about two completely different processes here, each with their own set of intricate protiens, pathways and genetic programming.
I mean what is photosynthesis? A conversion of light to chemical energy. In fact some plants move towards the sun, that's hardly a long step from simple sea-living animals moving towards the sun. http://en.wikipedia.org/wiki/HeliotropismIn fact there is animal heliotropism too. You can try to simplify this all you want. I'd recomend reading more articles regarding microbiology. we are finding things in cells at the microscopic level Darwin never even dreamt of.
How do you come to the conclusion that this is "darwinian dogma"? Because it was pure speculation based on a firm belief in evolution. Not any real, lab tested data.
This guy wanted a PhD on insect eyes and has one on crustacean eye optics, he's also a professor in zoology. And he's also written books on mathematics. It seems like you have to pay for his paper, but here's his homepage: http://www.biol.lu.se/funkmorf/vision/dan/Dan.html So? There are many people whith PhDs that disagree with many biological Darwinistic principles.
Which "we"? Certainly well educated scientists who work in that area seem to believe that this is significant. Yes and there are well educated scientists who work in that area that would question the significance as well.
The point is that they have an eye that has potential to be very accurate but the image is focused behind the retina. So the next step would be to further evolve this eye. So this looks like an intermediary stage in the evolution of the eye. Actually having this animal evolve in a lab in the direction of your choosing is not feasible. I have a slab of wood in my back yard that has the potential to be a tabletop for my family's dining room too.. So what? In this case I would have to mill, build and varnish it into a finished product. Likewise, In the case of intermediate biological eyes, we need a plausible mechanism to achieve that next level of complexity. Randomly mutating the codes that build the intermediate eye is no more likely to stumble upon somthing better than me doing random things to my slab of wood with various hand tools in my garage will build a tabletop.
Show me the emperically testable evidence please. That's what I've been trying to do, linking to countless fossils, transitional eyes, rudimentary eyes, primitive eyes, degenerate eyes, scientific theories, mathematical models, computer simulations and so on. http://en.wikipedia.org/wiki/Evolution_of_the_eye [/quote]
To me this is like trying to prove god exists by providing links to creationist sites. Biological Evolution is unfalsifyable and at the same time, unproveable. Just as God or even Zeus is..
We can't simulate or recreate the entire evolution of Earth in a lab. So we have to use the scientific method and figure out a theory that fits reality. I for one am not asking for the entire evolution of Earth in a lab. I'd be happy with one lab expiriment that demonstrates real time macro evolution of a species.
It's not a complete simulation of the evolution of live on Earth but a model of evolution. From where did you get that it's created to succeed?. Also the program is more than just IF THEN statements: The program, called Avida, is an artificial petri dish in which organisms not only reproduce, but also perform mathematical calculations to obtain rewards. Their reward is more computer time that they can use for making copies of themselves. Avida randomly adds mutations to the copies, thus spurring natural selection and evolution. The research team watched how these "bugs" adapted and evolved in different environments inside their artificial world. This is virtually the same program I spoke of. The enviornment, the mathematical calculations and the rewards are all set up ahead of time and the program is designed to succeed. If this were anything close to reality, we should be able to do the same thing in a lab with real biological organisms.
Didn't we just talk about things like nylonase? And genetically modified crops are big. Or what are you looking for? Nylonase.. C'mon man, really? Because Nylon never existed before thus bacteria "evolved" to utilize it as a food source? That's like saying because Twinkies were invented by humans and don't exist in the wild, humans evolved to eat them. How do we know that these bacteria didn't already eat some of these chemicals before hand? All products we make come from naturally occuring chemicals or coctails thereof.
And so we geneticly enhance crops.. Call me when we turn wheat into a newly evolved organism.
It's not speculation. I've given you sources to multiple examples of rudimentary eyes, transitional eyes, theories on the formation of eyes etc. Just because we can't be 100% sure of every detail on the developement of eyes doesn't mean the theory is all wrong and needs to be discarded. I'm not saying discard it.. In fact I'd love nothing more than to see it proven. A bicycle and a motorcycle in existence is not proof of one evolving into another anymore than a "simple" and "complex" eye. If you can't demonstrate a pathway then you have nothing but speculation.
I've given you multiple sources for this theory. Yes you have but every example is pure speculation around a centeral idea, nothing more.
Something as simple as picking up a rock and hitting a nut with it is using a basic tool. From there on our use of tools just accelerated. How? How did it "just accelerate"? Monkeys can poke sticks in antholes to get a tasty snack. There ya go.. tool use. I don't see their tool making skills accelerating do you? Monkeys will be poking sticks in ant holes millions of years from now unless somthing redesigns their brain to do more. And I'm sorry, but random mutation to the genes that build their brain is no more likely going to improve the situation than mutating the genes building our brains will give us any more improvement.
Many animals can stand on two legs well. And especially monkeys who really have great balance, you need that if you're living in trees. I can't think of any animal that doesn't have good balance.
Just like with the nipples I ask, do the erector pili have anything to do with that?
I think so but trying to do a search on the subject yields little. Seems intuitive that cold causes goosebumps and causes hard nipples as well. Perhaps I'll do a little empirical research on the subject when her and I hit the sheets tonite..
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jucce
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The scientists who found the fossils are openly stating that they look like missing links. I don't see the fact that we are finding new animals that doesn't fit in a specific position as a problem. That's because stating so isn't heresy in modern biology where Darwinism is the reigning paradigm. In any other branch of science, making such flimsy claims without solid scientifc data would be frowned upon. And nobody is saying there is a problem, just that the fossil record isn't providing the undeniable evidence predicted by Darwin. They are justifying their assessment of these as missing links with evidence.
Fossils are rare, fossil discovery rarer, fossils can be destroyed, the Earth is large and not much of it has been searched for fossils. Fossils are simply a rare find.
And the fact is that there are transitional fossils (and many more regular fossils), I've given you links to 47 on Wikipedia and more on other pages. Also we're constantly finding new ones.
They had more to go on that just its genome, it's in the article. Yes they did have more to go on than the Genome and the animal's "posture" which is measureable and demonstrateable real science... a firm belief in the "fact" of evolution.
Of course you can look at an animal's demeanor, its posture, how it hunts, how it feeds, its physical attributes and draw conclusions from that. Just compare ordinary cats and big cats for example. And they also mention it's behaviour while breeding and then there's the DNA tests. A collection of evidence that points in one direction.
No. I don't see how that's relevant. Modern mammals have an inner ear separated from their lower jaw that allows them to better hear air-borne sounds. Reptiles have an inner ear attached to their jaw to better sense vibrations on the ground.
Yanoconodon's inner ear, however, is in the back of the jaw, connected by cartilage. So what? This is evidence of different ears suited to the individual specie's enviornment. Extrapolating any further links comes soley from a firm belief in biological evolution and not any real world testable evidence. We see evolution both in the fossil records and around us on Earth. http://www.talkorigins.org/indexcc/CC/CC215.html
And when it comes to the Pakicetus, I don't see your problem. They examined the skull, found strong similarities between the teeth and the inner ear of other ceteceans. In fact only cetaceans have those same inner ear features. They found a skull of an ancient whale.. That is it. So what?
They've found complete skeletons of the Pakicetus. I guess you could say it's an ancient whale because it evolved into our modern day whales as the many physical similarities suggest.
No I don't agree that you can disregard all those probable transitional fossils with "superficial bone differences not outside the realm of limited, microevolution". Also, like I said, during the last years we've just been finding more and more of these. Of course when it comes to the Archaeopteryx for example we will probably never be 100% sure of a specific find, but the sum of the evidence does point in one direction.
How can you sum up a mere 46 fossils mostly made of bone fragments and come to any concrete conclusion? Think of the difference in skeletons of a grate dane, bulldog and a chiauaua alone..
Well first of all, we do have more than 46 transitionary fossils. Here are some more examples: http://www.talkorigins.org/indexcc/CC/CC200.html
Studying these fossils scientists have found similarities and clear developement of attributes of these animals. We can see how the animals have gradually evolved through the fossil record: http://www.talkorigins.org/indexcc/CC/CC216_1.html http://www.talkorigins.org/indexcc/CC/CC214.html http://en.wikipedia.org/wiki/Evolution_of_the_horse etc.
Considering the fact that we're constantly finding new fossils we've probably only scratched the surface.
Of course there isn't guesswork when you have a living, breathing example! What if they found a living Archaeopteryx ? Just like the Coelacanth, museums had all kinds of displays and scietists were convinced this animal represented evolution encarnate. When it was only known from the fossil record this was a slam dunk example of evolution.. That is until they found it living off the coast of Africa and quickly took down the exhibits and distanceed themseleves from this absolute embarassment! I don't know the full story of the coelacanths but of course mistakes can be made. But from there to saying that the entire theory of evolution is a mistake is a gigantic step. http://www.talkorigins.org/indexcc/CB/CB930_1.html
The eye is not perfect, take the blind spot for example. And it's no surprise that the attributes surrounding our eye have a use, that's why they were passed on to the next generation. Furthermore things like eyelids most likely came early in animal (eye) developement. What about the blindspot? It doesn't hinder us in anyway and mammals are thought to have some of the best eyesight in the animal kingdom. And it's not a matter wether or not the attributes surrounding our eye have a use or not, it's how did they evolve in the first place? It's one thing to wave the magic evolutionary wand and say things like " and then the first fishes or amphibians walked out onto dry land", but think of the multitudes of complexity that need to be in place and working before this is even possible. Were talking a completely different enviornment here. Tear ducts and eyelids for example were crucial for this step. Not to mention legs able to support the animal, lungs to breathe etc. This would be about like humans evolving to walk on the lunar surface.
Well surely a perfect creation wouldn't have a spot in the field of vision where we're blind? We can't really judge how it would benefit us to not have a blind spot, we have nothing to compare to. Also the eye is very vulnerable and prone to errors, just think about all the people wearing glasses.
Like I said, everything is gradual, and remember, over billions of years. The developement of fins to legs were due to the need to travel between drying puddles of water, the fish who couldn't make it to water died so the ones with the best prerequisites lived and passed on their genes. And here we come to the Tiktaalik and similar finds again where we can trace the evolution of limbs through the fossil record, whales and dolphins found with limbs/fins are also interesting: http://en.wikipedia.org/wiki/Tiktaalik http://en.wikipedia.org/wiki/Eusthenopteron http://en.wikipedia.org/wiki/Fishapod http://en.wikipedia.org/wiki/Image:Fishapods.jpg http://www.talkorigins.org/indexcc/CC/CC216_1.html http://www.foxnews.com/story/0,2933,227572,00.html
Snakes for example have different system than us, they have transparent eyelids (or the equivalent) permanently attached to their eye with fluid underneath. Fish who feed in sandy or muddy areas can have this "spectacle" similar to what snakes have. Also take a look at adipose eyelids, they are a kind of eyelids for fish.
When it comes to lungs I believe some fish developed the ability to swallow air and "digest" it, taking the oxygen in their digestive system, perhaps to survive longer on journeys on land or in a dried up puddle. From there it evolved to a separate pocket for air and so on.
Like I said, I don't know exactly how simply a cell would have to be to be able to register light and I doubt you do either. It would definitely be less complicated than the cells in our eyes. In fact there are animals today who have very simple photo-sensitive cells, just simple enough to detect light. There is nothing simple about any living cell found anywhere at any time. There is no reason to suspect that the cells found inside say a trilobite are any less complicated than any cell found living today. The ONLY reason we would ever expect to find simpler versions of cells is in light of evolutionary theory. One interesting things is that for example simple alkali salts and silver halides are light-sensitive. Also some plants can amass photosensitive substances: http://en.wikipedia.org/wiki/Photosensitivity_in_animals
I'm just saying that the cells in our eyes are more advanced than the ones in a jellyfish for example. And there are many different types of cells, take mycoplasma for example: http://en.wikipedia.org/wiki/Mycoplasma
That proves there was light sensitive chemistry around. If photosynthesis could arise then surely light sensitivity in cells could. And the reason I simplify it as light sensitivity is because there was a gradual evolution from there. We are still talking about two completely different processes here, each with their own set of intricate protiens, pathways and genetic programming.
Well, like I tried to point out in my last post, I don't think they're that separate. Here's some more on that: http://www.herbalgram.org/default.asp?c=algaerestoresvision
I mean what is photosynthesis? A conversion of light to chemical energy. In fact some plants move towards the sun, that's hardly a long step from simple sea-living animals moving towards the sun. http://en.wikipedia.org/wiki/HeliotropismIn fact there is animal heliotropism too. You can try to simplify this all you want. I'd recomend reading more articles regarding microbiology. we are finding things in cells at the microscopic level Darwin never even dreamt of.
I'm not surprised, Darwin did his work about 150 years ago, it's good that the theory of evolution is evolving from what we learn.
How do you come to the conclusion that this is "darwinian dogma"? Because it was pure speculation based on a firm belief in evolution. Not any real, lab tested data.
It wasn't pure speculation, he didn't just throw out some numbers but he did do serious work with this. However it would be unfeasible to confirm his conclusions if it would require watching the entire evolution of Earth. But it can be one piece of the puzzle, corroborated by other findings.
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« Last Edit: March 27, 2007, 01:47:33 pm by jucce »
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jucce
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This guy wanted a PhD on insect eyes and has one on crustacean eye optics, he's also a professor in zoology. And he's also written books on mathematics. It seems like you have to pay for his paper, but here's his homepage: http://www.biol.lu.se/funkmorf/vision/dan/Dan.htmlSo? There are many people whith PhDs that disagree with many biological Darwinistic principles.
With PhDs in relevant areas? I'm sure there are some but the theory of evolution is widely accepted in the scientific community.
Which "we"? Certainly well educated scientists who work in that area seem to believe that this is significant. Yes and there are well educated scientists who work in that area that would question the significance as well.
There are always people who question things. However much proof and the vast majority of the scientific community stand behind this idea.
The point is that they have an eye that has potential to be very accurate but the image is focused behind the retina. So the next step would be to further evolve this eye. So this looks like an intermediary stage in the evolution of the eye. Actually having this animal evolve in a lab in the direction of your choosing is not feasible. I have a slab of wood in my back yard that has the potential to be a tabletop for my family's dining room too.. So what? In this case I would have to mill, build and varnish it into a finished product. Likewise, In the case of intermediate biological eyes, we need a plausible mechanism to achieve that next level of complexity. Randomly mutating the codes that build the intermediate eye is no more likely to stumble upon somthing better than me doing random things to my slab of wood with various hand tools in my garage will build a tabletop.
I don't think you can compare those things. Can you imagine what would happen if you did that for 4 billion years? What would the results be? I mean roll a dice for 4 billion years, I'm sure you'd get some results that would be highly unlikely.
Show me the emperically testable evidence please. That's what I've been trying to do, linking to countless fossils, transitional eyes, rudimentary eyes, primitive eyes, degenerate eyes, scientific theories, mathematical models, computer simulations and so on. http://en.wikipedia.org/wiki/Evolution_of_the_eyeTo me this is like trying to prove god exists by providing links to creationist sites. Biological Evolution is unfalsifyable and at the same time, unproveable. Just as God or even Zeus is..
No I don't agree with either those things. However if you want to prove evolution wrong it would have to take some very significant discovery since there's so much evidence in favor of it.
We can't simulate or recreate the entire evolution of Earth in a lab. So we have to use the scientific method and figure out a theory that fits reality. I for one am not asking for the entire evolution of Earth in a lab. I'd be happy with one lab expiriment that demonstrates real time macro evolution of a species.
Something like this? http://www.talkorigins.org/faqs/faq-speciation.html There is not a single one on that page you can accept? However evolution does happen over long periods of time, being able to do it on cue in a lab is asking very much.
http://english.people.com.cn/200606/16/eng20060616_274556.html http://www.sciencedaily.com/releases/2002/12/021202071449.htm Perhaps those?
It's not a complete simulation of the evolution of live on Earth but a model of evolution. From where did you get that it's created to succeed?. Also the program is more than just IF THEN statements: The program, called Avida, is an artificial petri dish in which organisms not only reproduce, but also perform mathematical calculations to obtain rewards. Their reward is more computer time that they can use for making copies of themselves. Avida randomly adds mutations to the copies, thus spurring natural selection and evolution. The research team watched how these "bugs" adapted and evolved in different environments inside their artificial world. This is virtually the same program I spoke of. The enviornment, the mathematical calculations and the rewards are all set up ahead of time and the program is designed to succeed. If this were anything close to reality, we should be able to do the same thing in a lab with real biological organisms.
No I don't agree, if you reason like that we should be able to do all things we can with computers in the real world.
Didn't we just talk about things like nylonase? And genetically modified crops are big. Or what are you looking for? Nylonase.. C'mon man, really? Because Nylon never existed before thus bacteria "evolved" to utilize it as a food source? That's like saying because Twinkies were invented by humans and don't exist in the wild, humans evolved to eat them. How do we know that these bacteria didn't already eat some of these chemicals before hand? All products we make come from naturally occuring chemicals or coctails thereof. And so we geneticly enhance crops.. Call me when we turn wheat into a newly evolved organism.
Well those particular byproducts didn't exist before the invention of nylon. I don't think your allegory is apt, it would be more like humans evolving to be able to digest cellulose or some new material like styrofoam.
And when it comes to speciation here are some more examples: http://www.talkorigins.org/indexcc/CB/CB910.html
It's not speculation. I've given you sources to multiple examples of rudimentary eyes, transitional eyes, theories on the formation of eyes etc. Just because we can't be 100% sure of every detail on the developement of eyes doesn't mean the theory is all wrong and needs to be discarded. I'm not saying discard it.. In fact I'd love nothing more than to see it proven. A bicycle and a motorcycle in existence is not proof of one evolving into another anymore than a "simple" and "complex" eye. If you can't demonstrate a pathway then you have nothing but speculation.
The fossils we have discovered show a clear pattern of evolution and transition between species. There are also much other corroborating evidence, it's an entire part of science. We have to look where the sum of the evidence points.
I've given you multiple sources for this theory. Yes you have but every example is pure speculation around a centeral idea, nothing more. Yes they extrapolate from a central theory (basically back at the theory of evolution) and of what we know of our world.
Something as simple as picking up a rock and hitting a nut with it is using a basic tool. From there on our use of tools just accelerated. How? How did it "just accelerate"? Monkeys can poke sticks in antholes to get a tasty snack. There ya go.. tool use. I don't see their tool making skills accelerating do you? Monkeys will be poking sticks in ant holes millions of years from now unless somthing redesigns their brain to do more. And I'm sorry, but random mutation to the genes that build their brain is no more likely going to improve the situation than mutating the genes building our brains will give us any more improvement. If you could use tools well you could protect yourself better and get food easier, so the propensity for tool use and intelligence was passed on.
Well the idea is that monkeys like chimpanzees and humans come from a common ancestor, and as they continue evolving they may evolve to become more intelligent, but it's no guarantee of course.
And humans are still evolving, I mentioned that AIDS resistance before if you recall. http://www.talkorigins.org/indexcc/CB/CB928_2.html
Many animals can stand on two legs well. And especially monkeys who really have great balance, you need that if you're living in trees. I can't think of any animal that doesn't have good balance. Very simple animals just float along the current so they don't really need balance and then there are animals who don't move. Having good balance is easier with four legs too. It can be hard to judge for example with animals like octopuses.
Just like with the nipples I ask, do the erector pili have anything to do with that?
I think so but trying to do a search on the subject yields little. Seems intuitive that cold causes goosebumps and causes hard nipples as well. Perhaps I'll do a little empirical research on the subject when her and I hit the sheets tonite.. Here's some good stuff http://en.wikipedia.org/wiki/Erection
What I'm basically trying to say is that the evidence points in one direction; the fossil record, clear signs of evolution in the fossil record, microevolution all around us, examples of speciation, DNA and genetic analysis, geological finds, attributes of current animals and so on.
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« Last Edit: March 27, 2007, 12:59:07 pm by jucce »
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RTyp06
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They are justifying their assessment of these as missing links with evidence. The evidence is flimsy and they are forcing the animals into their pre-defined paradigm. Funny how when religious scientists judge the evidence to fit their sacred texts they are ridiculed and scorned by main stream science, yet aren't evolutionists basicly doing the same thing? Science isn't supposed to be completely biased and one of the first scientific rules in any scientific field is not to fall in love with a paradigm.
We are all biased. Including myself. I admit it. But at least I aknowledge this and go to great efforts not to make completely biased arguments. (I'll admit I may have slipped from time to time)
To me, science should state the facts,present the evidence and suggest an explanation when warrented. And It's certainly ok to suggest evolutionary pathways since that is the reigning paradigm, but when you strat overreaching the evidence and begin building fantastic just-so stories, it's too much in my opinion.
Fossils are rare, fossil discovery rarer, fossils can be destroyed, the Earth is large and not much of it has been searched for fossils. Fossils are simply a rare find. I do agree that the fossil record is incomplete but not to the degree most evolutionists do. Even so, I think we can gleen a pretty clear picture of life's history from it. The most predominate feature of the fossil record is stasis. Animals remain virtually unchanged for millions upon millions of years. For example we've found ancient bacteria preserved in salts dating to the earliest examples of life that are identical to today's bacteria.
And the fact is that there are transitional fossils (and many more regular fossils), I've given you links to 47 on Wikipedia and more on other pages. Also we're constantly finding new ones. "Transitional fossil" is a far overused term in palentology. They base these claims largely on bone differences alone and they extrapolate this from a belief in evolution. The same species of any given animal can have bone differences from the natural variation built into the animal's genome. But as I've said before, all breeding seems to show limits. To extrapolate these naturally occuring breeding variables into huge morphic changes goes beyond the science in my opinion.
Of course you can look at an animal's demeanor, its posture, how it hunts, how it feeds, its physical attributes and draw conclusions from that. Just compare ordinary cats and big cats for example. And they also mention it's behaviour while breeding and then there's the DNA tests. A collection of evidence that points in one direction. We disagree, it doesn't point in "one" direction. All big cats can interbreed. Lions, Tigers, Leapords, Cheetahs etc. Look at the diversity of these animals. Yet since they can interbreed, they are the same species of animal. Now it is possible that certain breeds will survive better in different environments and it may even be true that isolated from eachother long enough that they can no longer interbreed and indeed become a different species. (This could be the explanation of house cats if they can't breed with their big cousins) The problem I have is that I don't think cats will be anything but cats no matter how many millions of years you give it.
They've found complete skeletons of the Pakicetus. I think you need to check again because, if they have, I have yet to see it..
talkorigins is committed to Biological Evolution and Wikipedia is very biased in favor of Evolution. In fact Wikipedia is starting it's own version of the talkorigins site.
Considering the fact that we're constantly finding new fossils we've probably only scratched the surface. This probably is correct but I don't think fossilized bones will ever give us the detail we need to draw a conclusion either way.
I'm not saying the entire theory of evolution is a mistake. If I have led you to believe so then I apologize. Actually Im not really an antievolutionist in the traditional sense, I just feel that evolutionary biologists are way overstepping the scientific evidence to bolster their theories. Also, the real main gripe I have isn't the theory itself, which in all honesty isn't that unplausible, but the random, naturalistic mechanisims that supposidy drive it.
Well surely a perfect creation wouldn't have a spot in the field of vision where we're blind? I do not recall saying that the eye was a "perfect creation".
We can't really judge how it would benefit us to not have a blind spot, we have nothing to compare to. Also the eye is very vulnerable and prone to errors, just think about all the people wearing glasses. Yes, we cannot judge the eye at all. Scientists like Dawkins likes to point out "flaws" in the eye to combat creationists (of which I am not) with such things as backward facing rods and cones. He argues that no designer in his right mind would engineer an eye in such a way. But how can we judge somthing we cannot even come close to building within our limited human technology? Their may be an as of yet undiscoverd "reason" for such a feature. Perhaps somthing as simple as we are more prone to looking at the sun and this is a protection feature?
Like I said, everything is gradual, and remember, over billions of years. The developement of fins to legs were due to the need to travel between drying puddles of water, the fish who couldn't make it to water died so the ones with the best prerequisites lived and passed on their genes.
The problem here isn't that this scenario is improbable, just that it's pure speculation based around the idea of evolution. There really isn't any true scientific observations to justify this just-so story. It's an interesting idea to be sure, but not really rooted in any sort of scientifc fact.
I read through several of these and it's all pretty much the same as your other links. The Dolphin with an extra set of fully functional fins is interesting, but linking these anomolous fins to ancesteral legs is a stretch.
Snakes for example have different system than us, they have transparent eyelids (or the equivalent) permanently attached to their eye with fluid underneath. Fish who feed in sandy or muddy areas can have this "spectacle" similar to what snakes have. Also take a look at adipose eyelids, they are a kind of eyelids for fish. Fascinating but not very conclusive.
When it comes to lungs I believe some fish developed the ability to swallow air and "digest" it, taking the oxygen in their digestive system, perhaps to survive longer on journeys on land or in a dried up puddle. From there it evolved to a separate pocket for air and so on. Do we have scientific evidence of fish swallowing air and digesting it? And even if they did, it's a far stretch to think this behavior evolved into lungs which are very specific and complicated organs. Even if we have examples of "intermediate eyes" do we have evidence of intermediate lungs?
I'm just saying that the cells in our eyes are more advanced than the ones in a jellyfish for example. That's a nice belief. But that's all it really is at this point, a belief. Wether somthing is "more adavanced" or not is speculative and heavily biased by human intrepretation.
I'm not surprised, Darwin did his work about 150 years ago, it's good that the theory of evolution is evolving from what we learn. Well it pretty much has to evolve because in my opinion, we've made scientifc discoveries that provide quite a pickle for pure, random gradualism.
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RTyp06
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With PhDs in relevant areas? I'm sure there are some but the theory of evolution is widely accepted in the scientific community. Just because somthing is "widely accepted" doesn't make it fact. At one time the scientific paradigm was that the earth was the center of the universe. Or that the universe was satic and unchanging. Or that the world was flat. Or that heavier than air vehicles were uncapable of flying. etc.
There are always people who question things. However much proof and the vast majority of the scientific community stand behind this idea. Do we have polls to confirm this? I suspect most scientists are mainly concerned with their field of science and are indifferent to the theory of evolution. I suspect that most people believe the theory not because they can actually see how it works, but because they were indoctrinated throughought school and college science courses. Any sort of opposition to the theory is not allowed into science cirriculums, even if their arguments are purely scientific.
What's sad is that school science texts are still presenting erroneous material that has been known to be false for decades. Once more, lawsuits have become the ally of the evolutionists against anybody wanting to change the status quoe. Why would a theory so well rooted with scientific fact and with such concrete scientifc underpinnings be concerned in the least? I'm a firm believer in teaching the controversy and allowing students to explore critical thinking rather than leading them down a specifc pathway. There is controversy amongnst the scientists and it shouldn't be hidden imo.
I don't think you can compare those things. Can you imagine what would happen if you did that for 4 billion years? What would the results be? I mean roll a dice for 4 billion years, I'm sure you'd get some results that would be highly unlikely. Yes I may. But multicelled life is only thought to have been here for 550 to 600 million years and vertebrate animals thought to have crawled out of the ocean around 300 million years ago. Also, at the microscopic level, all biological features are carefully crafted by specific sequences of chemical codes. If scientists could just randomly throw DNA codes together and produce somthing viable, your argument would hold more weight. We know this is not the case.
No I don't agree with either those things. However if you want to prove evolution wrong it would have to take some very significant discovery since there's so much evidence in favor of it. That's just it, you cannot prove it wrong because it's nothing more than an idea. Here's a park table with built in benches and an umbrella:
First rectangle planks sat side by side on the ground. Then crossplanks formed to hold the top planks togther. Then it began growing crossed legs at the four corners. As it got taller and taller people could no longer reach it's surface to enjoy their meal. so this nessicated chairs (similar evolutionary chair story here). Then a hole evolved in the middle to support an unbrella to protect patrons from rain and provide shade from the sun. etc. etc.
The point is that anything can be evolved with enough imagination, and unfortunately, we see alot of this in scientific articles.. Assuming we didn't know that park tables were manufactured by humans, how can my story be falsified?
I'm not sure you know what macroevolution is..
http://en.wikipedia.org/wiki/Macroevolution
No I don't agree, if you reason like that we should be able to do all things we can with computers in the real world. Well not really. Chemical coded life is informational in nature. Computers are informational in nature. there is a much higher corellation between the two. Computers can easily be used to manipulate amino acid sequences. These new sequences can then be sequenced into the genome of a species. This is reality in the 21st century and is in fact being done. Companies are putting patents on designer genes in fact.
Now, If those evolutionary programs you linked to were a representation of natural evolution, we should be able to easily evolve organisms in the same way and then sequence the results into living examples of evolution.
Well those particular byproducts didn't exist before the invention of nylon. I don't think your allegory is apt, it would be more like humans evolving to be able to digest cellulose or some new material like styrofoam. Bacteria are amazing little creatures and can adapt to pretty much any enviornment. I believe this is a clear case of microevolution.
The fossils we have discovered show a clear pattern of evolution and transition between species. There are also much other corroborating evidence, it's an entire part of science. We have to look where the sum of the evidence points. I disagree that a "clear pattern" is shown.
If you could use tools well you could protect yourself better and get food easier, so the propensity for tool use and intelligence was passed on. Can this philosophy be demonstrated in a lab?
Well the idea is that monkeys like chimpanzees and humans come from a common ancestor, and as they continue evolving they may evolve to become more intelligent, but it's no guarantee of course. I'm aware of the idea. So do you think that any races of humans are more or less evolved than any others?
Microevolution. No new species of human just a unique trait of some individual's immune system.
Very simple animals just float along the current so they don't really need balance and then there are animals who don't move. Having good balance is easier with four legs too. It can be hard to judge for example with animals like octopuses. Ok, I meant land animals.
What I'm basically trying to say is that the evidence points in one direction; the fossil record, clear signs of evolution in the fossil record, microevolution all around us, examples of speciation, DNA and genetic analysis, geological finds, attributes of current animals and so on.
"fossil record", "clear signs of evolution in the fossil record", and "geological finds" all seem to be the same thing. I disagree that the fossil records shows "clear signs" of anything other than a robust diversity of past life and remarakable stasis of these animals. As for microevolution, this is breeding differences due to variables programmed into the genome. Speciation as you've linked previously is nothing more than microevolution. Attributes of current animals? I'm not sure what you are driving at here.
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« Last Edit: March 29, 2007, 05:26:34 am by RTyp06 »
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Death 999
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We did. You did. Yes we can. No.
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We disagree, it doesn't point in "one" direction. All big cats can interbreed. Lions, Tigers, Leapords, Cheetahs etc. Look at the diversity of these animals. Yet since they can interbreed, they are the same species of animal. The offspring are infertile. They are different species.
They've found complete skeletons of the Pakicetus. I think you need to check again because, if they have, I have yet to see it.. Wouldn't that mean that you should check again?
Also, the real main gripe I have isn't the theory itself, which in all honesty isn't that unplausible, but the random, naturalistic mechanisims that supposidy drive it. What drives evolution is part of the theory.
Perhaps somthing as simple as we are more prone to looking at the sun and this is a protection feature? The nerves which are supposedly doing the shielding in this explanation are also susceptible to radiative damage. In fact, if they get damaged, it's worse.
The problem here isn't that this scenario is improbable, just that it's pure speculation based around the idea of evolution. There really isn't any true scientific observations to justify this just-so story. It's an interesting idea to be sure, but not really rooted in any sort of scientifc fact. "Just-so" stories are completely made up myths which are not believed by the storyteller to get a kid to shut up and give a moral lesson. The theory of evolution is the result of two observations: 1 A mechanism which definitely exists would produce it. 2 The observations of ancient animals fit this pattern. While using the term to refer to specific branches with little evidence, the overall picture is NOT one. Even if it happens to be wrong, it's not a Just-So story.
I read through several of these and it's all pretty much the same as your other links. The Dolphin with an extra set of fully functional fins is interesting, but linking these anomolous fins to ancesteral legs is a stretch. Why?
Snakes for example have different system than us, they have transparent eyelids (or the equivalent) permanently attached to their eye with fluid underneath. Fish who feed in sandy or muddy areas can have this "spectacle" similar to what snakes have. Also take a look at adipose eyelids, they are a kind of eyelids for fish. Fascinating but not very conclusive. Okay, try this on, then: snakes have infrared detectors on the sides of their faces. There is NO LENS. There is only a sharp edge, which they can sweep across the field of view by swaying their head. A set of experiments revealed that they were able to detect rabbits from fairly similarly shaped warm objects, just by this very crude method, due to appropriate neural processing. So, having a lens at ALL is actually optional. A lens does improve matters, to be sure.
Do we have scientific evidence of fish swallowing air and digesting it? And even if they did, it's a far stretch to think this behavior evolved into lungs which are very specific and complicated organs. Even if we have examples of "intermediate eyes" do we have evidence of intermediate lungs? Yes. Ever heard of 'book lungs' ? They're kind of crappy lungs, but they work fine as gills. Found on several fish, and in a few spiders.
I'm just saying that the cells in our eyes are more advanced than the ones in a jellyfish for example. That's a nice belief. But that's all it really is at this point, a belief. Wether somthing is "more adavanced" or not is speculative and heavily biased by human intrepretation. There are several reasonable definitions of 'advanced', and under several of them, the statement is correct. Stop nitpicking.
I'm not surprised, Darwin did his work about 150 years ago, it's good that the theory of evolution is evolving from what we learn. Well it pretty much has to evolve because in my opinion, we've made scientifc discoveries that provide quite a pickle for pure, random gradualism. And yet the theory, in being refined, has principally incorporated more details about the mechanism (gene changes) which have been discovered and verified - not just postulating them to explain otherwise inexplicable results. This kind of change is good science. Restricting the question to gradualism is a total straw man.
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Ragnorok
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I dont know if anyone has adressed this, but during the last Ice Age, the polar ice caps only came down as far south as London, hence nowhere near the modern habitat of crocodiles who have not significantly evolved since the age of the Dinosaurs because there is no mutation that would be favourable.
In other words crocs havent evolved because theyre perfectly adapted to their habitat, which has not significantly changed since the dinosaurs.
Not only do we have scientific evidence of fish breathing air, we have common examples in home tropical aquariums, Anabantoids, or Labyrinth fish. These include Gouramis, Siamese Fighting Fish and Climbing Perch who can crawl out of one body of water, into another, they have even been known to climb trees.
The lung like Labyrinth organ which enables these fish to breathe air would have primarily enabled the fish to survive in waters with low oxygen content, as a consequence some, like the climbing perch developed a land loving habit.
The only random aspect in the theory of evolution is genetic mutation, or a Darwin called it, variation, but observations support that. Natural Selection is also an observable fact, its simply one species causing a decline in another due to more advantageous characteristics.
We also observe the effects of Artificial Selection, where characteristics of domesticated species are promoted through selective breeding.
Goldfish are a typical example Sarasa Comets, Fantails, Orandas and Lionheads can all be traced back to the common goldfish, which in turn is a descendend of a Crucian Carp or similar fish, yet they look very different to their ancestors.
Charles Darwin noted the same kind of thing, but in pigeons at first, and then other domesticated species. Then on Galapagos, he famously noticed the same kind of thing happening to wild finches.
It is argued that a different shaped beak, or modified body shape may be reasonable, but for one type of creature to become an ancestor of another over time is not. The trouble is, on what basis can we draw a line? How can we define a limit in the change of characteristics of species over generations?
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jucce
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Hmm, sorry for my absence, I've had problems with my Internet connection. But it seems Death 999 answered some of the points and the discussion seems to have petered out?
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RTyp06
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The offspring are infertile. They are different species. Wrong. The Liger for instance produces females that can breed, it's just the male that is infertile. Hybrids are not always infertile. Take the Beefalo for instance:
http://en.wikipedia.org/wiki/Beefalo
It doesn't matter if the hybrid offspring are infertile anyway, how does that seperate them as species? As I said, the animals may drift away from one another genetically but the fact they can breed shows common ancestery which isn't a mystery at all. What is a mystery is morphical changes above the species level that has never been demonstarted.. well... ever.
Wouldn't that mean that you should check again? I have and my assertion still stands. This is another case of scientists extrapolating beyond the factual science.
What drives evolution is part of the theory. Of course it is.. This is where I have my biggest objections to evolutionary theory.
The nerves which are supposedly doing the shielding in this explanation are also susceptible to radiative damage. In fact, if they get damaged, it's worse. And you know this "fact" how?
I read through several of these and it's all pretty much the same as your other links. The Dolphin with an extra set of fully functional fins is interesting, but linking these anomolous fins to ancesteral legs is a stretch. Why? Why isn't it? Do these fins look anything like legs to you?
Okay, try this on, then: snakes have infrared detectors on the sides of their faces. There is NO LENS. There is only a sharp edge, which they can sweep across the field of view by swaying their head. A set of experiments revealed that they were able to detect rabbits from fairly similarly shaped warm objects, just by this very crude method, due to appropriate neural processing. So, having a lens at ALL is actually optional. A lens does improve matters, to be sure. So I guess the fact that snakes have eyes is completely redundant then? Sharks can detect electromagnetic fields of prey. Ducks and geese can detect the magnetic poles of the earth. Some insects can detect ultraviolet light. In light of this, I don't think you have a point here.
There are several reasonable definitions of 'advanced', and under several of them, the statement is correct. Stop nitpicking. No the statement is not correct and I am not nitpicking. What makes us more complex than bacteria is that we have multiple cells working in conjunction to achieve specific functions and pathways where the bacteria do not. I'd argue that the single cell by itself is no more or less complex or "advanced" in either example.
And yet the theory, in being refined, has principally incorporated more details about the mechanism (gene changes) which have been discovered and verified - not just postulating them to explain otherwise inexplicable results. This kind of change is good science. Restricting the question to gradualism is a total straw man.
Just because genes change doesn't mean we can accurately extrapolate this into macro changes beyond the species level. The more we study these genetic changes that occur in all species, the more we are finding that they are purposeful and useful to the species.
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Death 999
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We did. You did. Yes we can. No.
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The Liger for instance produces females that can breed, it's just the male that is infertile. Hybrids are not always infertile. Even half of them being infertile is not a characteristic you would expect of individuals in the same species.
But really, let's look at how big this category you've drawn is: it says that servals, caracals, lions, and tigers are not merely related, but the same species (there are some serious differences between these, just look). The 'they're still just cats' statement is empty. Yes, they are cats. There's no reason they shouldn't be. Every theory produces their being, in fact, cats. In evolution, this is because being a cat has, so far, worked. When being a cat breaks down we'll see some larger changes, or they'll die out. As for having no surviving close relatives except each other, there's no problem with that. Are you claiming there is one?
The nerves which are supposedly doing the shielding in this explanation are also susceptible to radiative damage. In fact, if they get damaged, it's worse. And you know this "fact" how? The nerves in the front gather, process, and transport information from multiple photon-receiving nerve cells. If one of these is cut off, then one kind of information from many light-sensitive cells is cut off. One detection cell is not as critical.
Why isn't it? Do these fins look anything like legs to you? The point was not that these fins are legs, the point was that clearly large morphological changes can occur, and maintain functionality. So, your statement is irrelevant to the claim being made. Especially since the changes we are really talking about are thousands of times more gradual and thus possible to accomplish with accumulated slight changes, as opposed to this change.
So I guess the fact that snakes have eyes is completely redundant then? 1) Being able to see in the dark is useful. These are infrared detectors. 2) Even if it were redundant, their existence still proves the point I was attempting to make.
This grievous misinterpretation does not inspire me to read any further.
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jucce
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They are justifying their assessment of these as missing links with evidence. The evidence is flimsy and they are forcing the animals into their pre-defined paradigm. Funny how when religious scientists judge the evidence to fit their sacred texts they are ridiculed and scorned by main stream science, yet aren't evolutionists basicly doing the same thing? Science isn't supposed to be completely biased and one of the first scientific rules in any scientific field is not to fall in love with a paradigm. We are all biased. Including myself. I admit it. But at least I aknowledge this and go to great efforts not to make completely biased arguments. (I'll admit I may have slipped from time to time) To me, science should state the facts,present the evidence and suggest an explanation when warrented. And It's certainly ok to suggest evolutionary pathways since that is the reigning paradigm, but when you strat overreaching the evidence and begin building fantastic just-so stories, it's too much in my opinion. In which way are they making the evidence fit their paradigms? They're basing their theories on the evidence not the other way around.
What fantastic stories are they building?
Fossils are rare, fossil discovery rarer, fossils can be destroyed, the Earth is large and not much of it has been searched for fossils. Fossils are simply a rare find. I do agree that the fossil record is incomplete but not to the degree most evolutionists do. Even so, I think we can gleen a pretty clear picture of life's history from it. The most predominate feature of the fossil record is stasis. Animals remain virtually unchanged for millions upon millions of years. For example we've found ancient bacteria preserved in salts dating to the earliest examples of life that are identical to today's bacteria.
Yes naturally some life-forms look unchanged like the crocodiles or species of bacteria. But we're also seeing much change in the fossil record. And again, punctuated equilibrium makes the point that fossil formation of "transitional" stages are even more rare since evolution occurs in "bursts".
And the fact is that there are transitional fossils (and many more regular fossils), I've given you links to 47 on Wikipedia and more on other pages. Also we're constantly finding new ones. "Transitional fossil" is a far overused term in palentology. They base these claims largely on bone differences alone and they extrapolate this from a belief in evolution. The same species of any given animal can have bone differences from the natural variation built into the animal's genome. But as I've said before, all breeding seems to show limits. To extrapolate these naturally occuring breeding variables into huge morphic changes goes beyond the science in my opinion.
Well the theory of evolution is based on the evidence and the findings not the other way around. And naturally they base their claims a lot on bone differences because there's not much else to examine on a skeleton. It's interesting when we can follow certain features changing through the fossil record, there's alot out there: http://www.talkorigins.org/indexcc/CC/CC200.html
Of course you can look at an animal's demeanor, its posture, how it hunts, how it feeds, its physical attributes and draw conclusions from that. Just compare ordinary cats and big cats for example. And they also mention it's behaviour while breeding and then there's the DNA tests. A collection of evidence that points in one direction. We disagree, it doesn't point in "one" direction. All big cats can interbreed. Lions, Tigers, Leapords, Cheetahs etc. Look at the diversity of these animals. Yet since they can interbreed, they are the same species of animal. Now it is possible that certain breeds will survive better in different environments and it may even be true that isolated from eachother long enough that they can no longer interbreed and indeed become a different species. (This could be the explanation of house cats if they can't breed with their big cousins) The problem I have is that I don't think cats will be anything but cats no matter how many millions of years you give it.
According to biology they are different species. Whether or not they can interbreed isn't the only criteria for different species. Even if the offspring isn't sterile they may be different species. For example are they fertile only with the parent species or also with each other, are both the males and the females fertile and so on.
But really my point was that you can look at an animals demeanor and draw conclusions about it's close relatives. And that plus the DNA-test plus its behaviour while breeding points in one direction.
They've found complete skeletons of the Pakicetus. I think you need to check again because, if they have, I have yet to see it..
They did find complete skeletons. http://en.wikipedia.org/wiki/PakicetusComplete skeletons were discovered in 2001 Here's a site: http://darla.neoucom.edu/DEPTS/ANAT/Thewissen/whale_origins/whales/Pakicetid.html
talkorigins is committed to Biological Evolution and Wikipedia is very biased in favor of Evolution. In fact Wikipedia is starting it's own version of the talkorigins site.
Perhaps but they do give you sources and references. They're basically places that collect information, taking it from other sources.
Considering the fact that we're constantly finding new fossils we've probably only scratched the surface. This probably is correct but I don't think fossilized bones will ever give us the detail we need to draw a conclusion either way.
Well it's really never about a single find, it's the sum of evidence from different sources and of different kind that has to support a theory.
I'm not saying the entire theory of evolution is a mistake. If I have led you to believe so then I apologize. Actually Im not really an antievolutionist in the traditional sense, I just feel that evolutionary biologists are way overstepping the scientific evidence to bolster their theories. Also, the real main gripe I have isn't the theory itself, which in all honesty isn't that unplausible, but the random, naturalistic mechanisims that supposidy drive it.
What does feel wrong about it?
I've personally always thought it sounds reasonable. Random mutations and then they're "tested" in the field, and as a consequence the most beneficial ones remain. But there can of course be complex mechanisms within that like isolation and re-breeding between isolated groups and so on.
Well surely a perfect creation wouldn't have a spot in the field of vision where we're blind? I do not recall saying that the eye was a "perfect creation".
No I guess not. But you said:
We see precision and purpose from the most minute microscopic detial of our modern eye to the largest features such as eyelids, control muscles, tear ducts etc. And I was disagreeing with that.
We can't really judge how it would benefit us to not have a blind spot, we have nothing to compare to. Also the eye is very vulnerable and prone to errors, just think about all the people wearing glasses. Yes, we cannot judge the eye at all. Scientists like Dawkins likes to point out "flaws" in the eye to combat creationists (of which I am not) with such things as backward facing rods and cones. He argues that no designer in his right mind would engineer an eye in such a way. But how can we judge somthing we cannot even come close to building within our limited human technology? Their may be an as of yet undiscoverd "reason" for such a feature. Perhaps somthing as simple as we are more prone to looking at the sun and this is a protection feature?
Still if we can't judge our eye isn't your statement above excessive? And I think a detail like the blind spot is still a flaw. Either way the eye is far from perfect.
Like I said, everything is gradual, and remember, over billions of years. The developement of fins to legs were due to the need to travel between drying puddles of water, the fish who couldn't make it to water died so the ones with the best prerequisites lived and passed on their genes. The problem here isn't that this scenario is improbable, just that it's pure speculation based around the idea of evolution. There really isn't any true scientific observations to justify this just-so story. It's an interesting idea to be sure, but not really rooted in any sort of scientifc fact.
Well the science behind it is the theory of evolution and all the finds connected with that. We have fossils showing this development for example.
I read through several of these and it's all pretty much the same as your other links. The Dolphin with an extra set of fully functional fins is interesting, but linking these anomolous fins to ancesteral legs is a stretch.
Maybe if we only had that but the sum of the evidence is quite conclusive if you ask me.
Snakes for example have different system than us, they have transparent eyelids (or the equivalent) permanently attached to their eye with fluid underneath. Fish who feed in sandy or muddy areas can have this "spectacle" similar to what snakes have. Also take a look at adipose eyelids, they are a kind of eyelids for fish. Fascinating but not very conclusive.
It was just to point out that eylids for example wasn't necessarily a problem when venturing onto land. In fact even the early eyes surely had protection, it's not something that popped up. It most likely evolved in parallell with other features of the eye.
When it comes to lungs I believe some fish developed the ability to swallow air and "digest" it, taking the oxygen in their digestive system, perhaps to survive longer on journeys on land or in a dried up puddle. From there it evolved to a separate pocket for air and so on. Do we have scientific evidence of fish swallowing air and digesting it? And even if they did, it's a far stretch to think this behavior evolved into lungs which are very specific and complicated organs. Even if we have examples of "intermediate eyes" do we have evidence of intermediate lungs?
The Arapaima is an interesting fish, it has the capability to breath air.The fish also has the ability to breathe air from the surface due to a lung-like lining of its throat, an advantage in oxygen-deprived water that is often found in the Amazon River. This fish is therefore able to survive extensive drought periods by gulping air and burrowing in the mud or sand of the swamps. It sounds very much like the first air-breathing fish.
It's interesting to read about these things. Apparently many fish evolved the ability to breath air but not all ventured onto land just because of that. And it seems the swim-bladder can have ties to the lungs too. And also signs have been found of "marine anoxia" perhaps an explanation for why so many fish developed ways to breath air. Interesting when different discoveries intersect and corroborate each other.
http://en.wikipedia.org/wiki/Lungfish http://en.wikipedia.org/wiki/Rhipidistia http://www.skepticwiki.org/wiki/index.php/Intermediate_Forms_Between_Classes#Fish-amphibian_intermediates
Here's an entire lecture on the subject: http://www.csupomona.edu/~dfhoyt/classes/zoo138/PRIM_FISH.HTML
I'm just saying that the cells in our eyes are more advanced than the ones in a jellyfish for example. That's a nice belief. But that's all it really is at this point, a belief. Wether somthing is "more adavanced" or not is speculative and heavily biased by human intrepretation.
I don't know if it's biased. It's like saying a fat cell is less advanced than a brain cell. The cells in our eyes, giving us good vision is superior to those in a jellyfish who may only be able to separate light from dark to me.
I'm not surprised, Darwin did his work about 150 years ago, it's good that the theory of evolution is evolving from what we learn. Well it pretty much has to evolve because in my opinion, we've made scientifc discoveries that provide quite a pickle for pure, random gradualism. Yes it seems evolution is changing with new discoveries, just as it should be. However I'm not sure what you mean with "pure, random gradualism". Even punctuated equilibrium can be considered gradualism, just not with a constant rate. Even Darwin said:
"Many species, once formed, never undergo any further change...; and the periods, during which species have undergone modification, though long as measured by years, have probably been short in comparison with the periods during which they retain the same form."
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« Last Edit: April 04, 2007, 08:54:39 am by jucce »
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jucce
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With PhDs in relevant areas? I'm sure there are some but the theory of evolution is widely accepted in the scientific community. Just because somthing is "widely accepted" doesn't make it fact. At one time the scientific paradigm was that the earth was the center of the universe. Or that the universe was satic and unchanging. Or that the world was flat. Or that heavier than air vehicles were uncapable of flying. etc.
None of those ideas were as widely accepted as the theory of evolution. I'd say the theory of evolution is one of the most strongly supported in science and one of the most scrutinized.
There are always people who question things. However much proof and the vast majority of the scientific community stand behind this idea. Do we have polls to confirm this? I suspect most scientists are mainly concerned with their field of science and are indifferent to the theory of evolution. I suspect that most people believe the theory not because they can actually see how it works, but because they were indoctrinated throughought school and college science courses. Any sort of opposition to the theory is not allowed into science cirriculums, even if their arguments are purely scientific. What's sad is that school science texts are still presenting erroneous material that has been known to be false for decades. Once more, lawsuits have become the ally of the evolutionists against anybody wanting to change the status quoe. Why would a theory so well rooted with scientific fact and with such concrete scientifc underpinnings be concerned in the least? I'm a firm believer in teaching the controversy and allowing students to explore critical thinking rather than leading them down a specifc pathway. There is controversy amongnst the scientists and it shouldn't be hidden imo.
http://www.talkorigins.org/indexcc/CA/CA110.html
In all that time, the theory of evolution has only gotten stronger. Prior to the development of evolutionary theory, almost 100 percent of relevant scientists were creationists. Now the number is far less than 1 percent. And I don't think it's due to indoctrination, why would it? Opposition to the theory of evolution is allowed but what kind of opposition would you like to have in the curriculum?
If there are errors in the education that is bad of course. There is hardly any controversy between scientists about the validity of the theory of evolution. Perhaps some fine details are disputed but not the entire theory. But could you give an example of some fact you would like to be taught?
I don't think you can compare those things. Can you imagine what would happen if you did that for 4 billion years? What would the results be? I mean roll a dice for 4 billion years, I'm sure you'd get some results that would be highly unlikely. Yes I may. But multicelled life is only thought to have been here for 550 to 600 million years and vertebrate animals thought to have crawled out of the ocean around 300 million years ago. Also, at the microscopic level, all biological features are carefully crafted by specific sequences of chemical codes. If scientists could just randomly throw DNA codes together and produce somthing viable, your argument would hold more weight. We know this is not the case.
Well DNA wasn't thrown together from nothing to a complete lifeform. It evolved gradually retaining pieces that worked. And isn't this precisely what scientists have been trying to emulate in their labs, albeit with computer programs like we talked about earlier. If multi-celled life has only existed for about a billion years that's a very long time, you would get unintuitive results doing random actions for that long.
No I don't agree with either those things. However if you want to prove evolution wrong it would have to take some very significant discovery since there's so much evidence in favor of it. That's just it, you cannot prove it wrong because it's nothing more than an idea. Here's a park table with built in benches and an umbrella: First rectangle planks sat side by side on the ground. Then crossplanks formed to hold the top planks togther. Then it began growing crossed legs at the four corners. As it got taller and taller people could no longer reach it's surface to enjoy their meal. so this nessicated chairs (similar evolutionary chair story here). Then a hole evolved in the middle to support an unbrella to protect patrons from rain and provide shade from the sun. etc. etc. The point is that anything can be evolved with enough imagination, and unfortunately, we see alot of this in scientific articles.. Assuming we didn't know that park tables were manufactured by humans, how can my story be falsified?
Well we could look at fossils of park tables and compare them to contemporary tables for example. Also a table isn't alive either and so on. That analogy is kind of a stretch.
Microevolution over time... What is it you want to see?
No I don't agree, if you reason like that we should be able to do all things we can with computers in the real world. Well not really. Chemical coded life is informational in nature. Computers are informational in nature. there is a much higher corellation between the two. Computers can easily be used to manipulate amino acid sequences. These new sequences can then be sequenced into the genome of a species. This is reality in the 21st century and is in fact being done. Companies are putting patents on designer genes in fact. Now, If those evolutionary programs you linked to were a representation of natural evolution, we should be able to easily evolve organisms in the same way and then sequence the results into living examples of evolution.
Our understanding of genetic engineering is still in it's infancy, we've only been doing this kind of science for a few years. Countless genetic diseases still exist and so forth, I don't think we have the technological capability or know-how to do that. Precisely what would you like them to do?
Well those particular byproducts didn't exist before the invention of nylon. I don't think your allegory is apt, it would be more like humans evolving to be able to digest cellulose or some new material like styrofoam. Bacteria are amazing little creatures and can adapt to pretty much any enviornment. I believe this is a clear case of microevolution.
Ok, but don't stamp all of this with "microevolution" and reject it, I don't think that's reasonable. From the link you gave me yourself about macroevolution:
Within the Modern Synthesis school of thought, microevolution is thought to be the only mode of evolution (i.e. what is sometimes thought of as "macroevolution" actually consists of the compounded effects of microevolution - the only difference between them is one of time and scale). What kind of changes do you want to see more than for example speciation and significant changes in an organism like these bacteria?
The fossils we have discovered show a clear pattern of evolution and transition between species. There are also much other corroborating evidence, it's an entire part of science. We have to look where the sum of the evidence points. I disagree that a "clear pattern" is shown.
If we can clearly see how a part of an animal has evolved in the fossils, for example the legs of a horse, the fins of fish to limbs, and all other examples I've shown then that's not a pattern?
I just watched a program a couple of days ago about how we can see in many water living animals varying adaptations for life at sea from their land-living ancestors. Otters, sea-lions and seals for example. And one interesting thing they mentioned is that manatees even have nails on their flippers.
If you could use tools well you could protect yourself better and get food easier, so the propensity for tool use and intelligence was passed on. Can this philosophy be demonstrated in a lab?
Seeing if someone who can't use their hands is better or worse at getting food and protecting themselves? I think that could be shown easily. And naturally those individuals who could get food and protect themselves lived and procreated.
I also saw a theory on the program I watched, some signs pointed towards Africa being flooded due to continental shifts around that time. Have you ever seen a monkey cross water? They walk upright, so that was another theory of why human ancestors became bipedal. Just adaption to the environment through natural selection; evolution.
Well the idea is that monkeys like chimpanzees and humans come from a common ancestor, and as they continue evolving they may evolve to become more intelligent, but it's no guarantee of course. I'm aware of the idea. So do you think that any races of humans are more or less evolved than any others?
"Less evolved" how? For example people with black skin are more resistant to sun, the mutation that made people more AIDS resistant also benefit people in certain regions more: http://biology.plosjournals.org/perlserv?request=get-document&doi=10.1371/journal.pbio.0030397 People from Asia also have a lower rate of alcohol metabolism and so on, but what is your point?
How do you delimit races? Just by physical appearance?
Microevolution. No new species of human just a unique trait of some individual's immune system.
My point was simply that humans are evolving. I've given you many examples of speciation previously. And like I mentioned above, using microevolution to reject many things like you do isn't reasonable.
I would like to understand what you want to see. Speciation occurs through many steps of microevolution, the examples of speciation I've given you isn't macroevolution according to you. And scientists say that macroevolution is basically microevolution over time. So could you elaborate on what it is you want to see?
Very simple animals just float along the current so they don't really need balance and then there are animals who don't move. Having good balance is easier with four legs too. It can be hard to judge for example with animals like octopuses. Ok, I meant land animals.
Well good balance is pretty much a prerequisite for even living on land. However on that program I watched they showed the Tamandua, it used its tail like kind of a life line and it fell multiple times. But how do you even define bad balance? Animals have good enough balance to live as they live. A cow doesn't really need as good balance as some monkey swinging through the trees.
What I'm basically trying to say is that the evidence points in one direction; the fossil record, clear signs of evolution in the fossil record, microevolution all around us, examples of speciation, DNA and genetic analysis, geological finds, attributes of current animals and so on.
"fossil record", "clear signs of evolution in the fossil record", and "geological finds" all seem to be the same thing. I disagree that the fossil records shows "clear signs" of anything other than a robust diversity of past life and remarakable stasis of these animals. As for microevolution, this is breeding differences due to variables programmed into the genome. Speciation as you've linked previously is nothing more than microevolution. Attributes of current animals? I'm not sure what you are driving at here. Like I said, the fossil record shows animals evolving over time. Attributes of species changing to suit their new environment. How could the nylonase for example be pre-programmed to digest chemicals that hadn't even existed a couple of years prior? And if speciation is microevolution too then what is macroevolution? Attributes of current animals are vestigial organs for example.
What I mean is that when different pieces of the evidence, obtained in different fashion and from different areas of research, converge and corroborate one another it creates a sort of synergy.
I found a list of a collection of evidence for evolution: http://www.talkorigins.org/indexcc/CA/CA202.html There are far more extensive lists though, for example one of the links at the bottom of that page.
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