Friday, 5 December 2008

The Idiocy Of Creationism (part 2)

This is a continuation of a refutation of Harun Yahya's problems with evolution. Part 1 can be found here.

(7) Reptiles are not the ancestors of birds...
It's very well established in the scientific literature that birds are descended from dinosaurs. Archaeopteryx is considered an intermediate form because it contains both avian and saurian features. Archaeopteryx was not the first creature with feathers either, there are at present 20 different species of feathered dinosaurs. Archaeopteryx also had a reptilian tail - not seen in modern birds, a mouth full of sharp teeth, and three fingers with claws. There are several other transitional forms between dinosaur and bird including the Microraptor. Not to mention that flight has evolved several times independently including in mammals, insects, and other reptiles like pterosaurs which were not dinosaurs and were not ancestors of modern birds.


(8) Fish did not move onto the land...
This is another outright denial of evidence. Perhaps Mr. Yahya hasn't heard of Tiktaalik. Now this is possibly one of the best evidences for evolution ever found, it shows the predictive nature. In the fossil record there no amphibians until around 370MYA and lobed finned fish before then so palaeontologists knew to look in 375 million year old rock of the right type in order to find this intermediate form. It was predicted to be there, it was found to be there and it had the right morphology just as predicted.

As for coelacanth, it being a living fossil doesn't invalidate evolution. It doesn't matter when a species leaves the fossil record, but when it enters it. If the coelacanth was around in Precambrian rocks or early Cambrian long before any other vertebrates had developed, then it would be a problem. Instead it's place in the fossil record comes in after the vertebrates and after fish have developed. The coelacanth is exactly where it should be in the fossil record, and it's stasis in morphology in the fossil record is no objection to evolution. Indeed if it's an adapted form for it's environment, it would be odd to see macroscopic mutations that are more advantageous.

(9) Mutations cannot form new species...
The premise for this is all wrong, mutations naturally occur in all of us. They are simply copying errors in code. On average there are about 128 mutations in each of us, most of which are neutral and have no affect on our overall fitness. There are harmful mutations too, but harmful mutations tend to be deleterious and don't survive into subsequent generations. Then there are the occasional advantageous mutations, these increase the fitness of the organism and make it more likely to survive. In our own species we can trace back certain features to single mutations, like the mutation that allowed for blue eyes.

If mutation couldn't produce anything advantageous then there would be no need for the other 16 points of contention. Throw out heritable adaptation and natural selection and there is no Darwinian evolution; that's it, that's 150 years of science simply being wrong. But there are mutations that give an increased fitness, there are mutations that help the survival of an individual. It's important to remember that evolution works on a species level and not an individual, that mutations on an individual alone will not bring about a new species. Rather it is an accumulation of mutations over many generations.

(10) Natural selection cannot lead to evolution...Natural selection works with mutation in order to get evolution. Mutations happen, natural selection weeds out any of the bad mutations. It alone cannot lead to speciation, but it's a non-random selector of successful heritable traits. In the example of a zebra, if the fastest runner is so because of a mutation making it's legs better suited to running, then that trait will get passed down in it's offspring. Those without the mutation will be more prone to being targeted by predators so over time the zebras with the mutation will find itself in more and more of the population. But of course the predators also have the potential for mutations so faster or stronger predators would also be more suited to survival. This brings an evolutionary arms race, a driving factor in evolution.

As for the zebra is still a zebra remark, of course it is. Just as any offspring we have will be human, or any offspring a cat has will be a cat. The difference is that if two populations of cats are left for enough time and there is enough mutations of the right type then those populations will not be able to interbreed. Once you hit the species line, genetic differences really can't be shared and thus mutations will accumulate on each side and eventually there will be visible difference.

As stated earlier, if evolution could not act on natural selection or mutation then it would be game over. That's all the paper would have to show: that advantageous mutations are impossible and that natural selection is insufficient to weed out those bad mutations. Instead it's focusing on mute points that have nothing to do with the topic at hand.

(11) Human beings did not evolve, but were created as human beings...
There's just so much evidence that we did evolve. Humans have 46 chromosomes while the other primates have 48. So there are three options: the other primates all had chromosomes split, humans had chromosomes fused or we are wrong about common ancestry. Since we are the odd ones out, it should be us that has the fused chimpanzee chromosome. So when scientists mapped the human genome and the chimpanzee genome, we were able to look for this fused chromosome. And we found it. Now why would a fused chimpanzee chromosome be in our DNA if we were created as human beings? It comes down to the creator putting it there to trick us.

Of course there is going to be some overlap in the fossil record, again it doesn't matter where a species finishes in the fossil record, only where it enters. What's important is that Australopithecus come before homo habilis, which comes before homo erectus, which comes before both neanderthal and homo sapien. Dogs came from a single pack of wolves about 100,000 years ago, it would be fallacious to say that because there are still wolves that dogs didn't descend from wolves. Just as it would be fallacious to say that because there are still Africans that Europeans didn't have an African origin.

For the record:
  • Australopithecus (in various forms) - 4.2MYA to 1.1MYA
  • Homo Habilis - 2.4MYA - 1.5MYA
  • Homo Erectus - 1.8MYA - 0.3MYA
  • Homo Sapien - 0.5 MYA - present

(12) All the fossil skulls proposed for the supposed evolution of man are false...
Again, more lies. There skulls have intermediate characteristics including the size of the brain case, and the size and type of the jaw. For the distinction between apes and humans, all skulls are ape skulls. But to the point, it's interesting that homo habilis is classified as ape while homo erectus is classified as human because initially some scientists wanted to put homo habilis skulls in the same category as homo erectus. The skulls found show intermediate steps between older fossils and modern fossils, they show the gradual path to humanity. In fact there are so many skulls from different types of intermediate forms that scientists have to work out which ones are more likely candidates for our ancestry and which ones probably aren't. The problem for theists is that not a single one of these skulls should even exist.

6 comments:

Anonymous said...

and what about the 17th?

Kel said...

13 through 17 are on it's way.

Michael said...

Fish did not move onto the land...
This is another outright denial of evidence. Perhaps Mr. Yahya hasn't heard of Tiktaalik.


I believe your jumping to conclusions...It's a little more complex than that concerning Tiktaalik.

In Nature magazine it's argued by an evolutionist...

It is difficult to say whether this character distribution implies that Tiktaalik is autapomorphic,2 that Panderichthys and tetrapods are convergent, or that Panderichthys is closer to tetrapods than Tiktaalik. At any rate, it demonstrates that the fish-tetrapod transition was accompanied by significant character incongruence in functionally important structures.

Which basically means, if these fossils represent an evolutionary line from fish to tetrapod, the features are all mixed up and out of sequence – including the “functionally important structures.”

Tiktaalik a missing link? Nope!

Kel said...

The Missing Link is an outdated concept that referred to a form between apes and humans. Tiktaalik is not a missing link, it's an intermediate form.

Whether it's an ancestor of modern tetrapods is irrelevant, what's important about Tiktaalik is that it shows the transitional stages between fish and tetrapods, it has tertapod ribs, lungs and it's the first instance of a neck in the fossil record. It also had load-bearing wrists, and a combination between fish and tetrapod structures such as the ear. It's the very definition of a transitional form.


Now Tiktaalik is a triumph of interdisciplinary science. Thanks to palaeontology, we knew what age to look in. Thanks to geology, we knew where in the world those rocks are and of what kind of rocks they are. And the predictions of evolutionary biology demanded the type of structure to look for. It just so happens that it was found right where it was predicted to be. And it's just one of so many pieces of evidence that all point to our fishy origins.

Citizen Z said...

Which basically means, if these fossils represent an evolutionary line from fish to tetrapod, the features are all mixed up and out of sequence – including the “functionally important structures.”

You seem to be taking that section out of context. Here's the abstract for the paper:

http://www.nature.com/nature/journal/v456/n7222/full/nature07339.html

It is quite clearly a paper about the distal radials of the dorsal fin. They are not talking about Tiktaalik in toto, they are talking about the fins being different. Which isn't some evolution-denying discovery, transitional fossils are expected to have some differences.

There's also this news article about the paper in question. Not only does it not support a creationist interpretation, it is yet another of extremely strong evidence in favor of evolution:

"This was the key piece of the puzzle that confirms that rudimentary fingers were already present in the ancestors of tetrapods,'' said lead author Catherine Boisvert, also of Uppsala University.

(P.S. Failing to link your citations is poor form.)

Anonymous said...

Kel,

Email me. I have something for you that you expressed interest in elsewhere, which I can email by return.

Emmet.