13 May, 2009

Did someone ask for transitional fossils?

A common claim by creationists is that there are 'no transitional fossils', despite advice from their own people to stop using this argument. These claims are often made in a blog or forum comment section rather than on an official website, since it is clearly a ludicrous statement. They also crop up a lot in comments on YouTube videos alongside such gems as 'If we evolved from monkeys, why are there still monkeys?'. (The mindset of the claimant is usually clear enough due to the accompanying derogatory statements about Barack Obama and/or homosexuals.)

Anyway back to my point, transitional fossils. This is one of my favourite photos:



Skull A is that of a modern day chimpanzee, the closest living relative to humans, which are represented by Skull N (Edit: For those who claim there is no proof of the relationship between humans and chimps, see here - prepare to be pwned). Since evolutionary theory predicts that humans and chimps share a common ancestor, there necessarily must have been hominid-like organisms in the past with intermediate morphologies between the two modern day species. Now look at all the other skulls. Pretty convincing evidence if you ask me. Here is a list of the species for each skull and the given dates for their ages:

(A) Pan troglodytes, chimpanzee, modern
(B) Australopithecus africanus, STS 5, 2.6 My
(C) Australopithecus africanus, STS 71, 2.5 My
(D) Homo habilis, KNM-ER 1813, 1.9 My
(E) Homo habilis, OH24, 1.8 My
(F) Homo rudolfensis, KNM-ER 1470, 1.8 My
(G) Homo erectus, Dmanisi cranium D2700, 1.75 My
(H) Homo ergaster (early H. erectus), KNM-ER 3733, 1.75 My
(I) Homo heidelbergensis, "Rhodesia man," 300,000 - 125,000 y
(J) Homo sapiens neanderthalensis, La Ferrassie 1, 70,000 y
(K) Homo sapiens neanderthalensis, La Chappelle-aux-Saints, 60,000 y
(L) Homo sapiens neanderthalensis, Le Moustier, 45,000 y
(M) Homo sapiens sapiens, Cro-Magnon I, 30,000 y
(N) Homo sapiens sapiens, modern

Now the photo is slightly misleading in that it suggests a steady progression from chimps to humans. This is not how evolution happened. The chimp and human lineages split about 5-7 million years ago and so predate the above photo. The chimp skull is just there for reference. The comparisons should really be studied from B-N, that is from Australopithecus to humans. A similar diagram could be made tracking the evolution to the modern day chimp, but the differences may be less obvious. In fact, at a glance, the modern chimp skull is actually quite similar to Australopithecus (although there are many differences, look at the eye sockets).

Another thing to point out is that these particular skulls may not have belonged to individuals that were direct ancestors of modern humans, they may well have been on other branches on the hominid evolutionary tree (see picture below). This is not really a problem though, as it is simply like comparing similarities between aunts, uncles and cousins, instead of directly comparing parents and offspring. The point being that comparisons can still be informative and a range of transitional features from modern day chimps to modern day humans is evident, indicative of common ancestry. Of course, the fact still remains that many of the species above could have belonged to populations that were direct ancestors of modern day humans.


Hominid evolution (including Kent Hovind, proponent of the 'no transitional fossil' argument)

Tracking the changes in the skull between Australopithecus and humans, we can notice gradual changes which would be considered transitional. Notice how the palate (roof of the mouth) retracts over time, indicating that less strength was needed to chew food. Although not visible on the above photo, the lower jawlines of these early hominid skulls are even more pronounced and follow a similar pattern of change.

This is most likely a direct result of the use of fire, as cooked food is much easier to breakdown and chew than raw meat and plants. It is thought that Homo habilis invented the use of fire for cooking, and accordingly it is the Homo habilis skull (Skull E) which first shows a reduced size in the palate.

Also, notice how the brain size increases massively in a steady progression from Australopithecus to humans. One hypothesis actually links these two morphological changes. Is is thought that a mutation in a protein called MYH16, a chief component of the powerful jaw muscles, resulted in a reduction in the size of the chewing apparatus. This may have reduced the physical restraints on the rest of the skull, allowing it to grow and accommodate the increasing size of the brain.

All fascinating stuff!

Now how on earth can a creationist look at these skulls and claim that there are no transitional fossils? Well some claim that this is just evidence of 'variation within kinds' or that transitional fossils must be direct ancestors and not from other branches. These claims are weak. Firstly, if it only represents 'variation within kinds' then these creationists are still conceding that chimps and humans are the same 'kind', in direct contradiction to their faith. Secondly, no evolutionist claims that transitional fossils must be from direct ancestors, merely that they show transition between the morphology of a particular feature in two distinct specimens. These changes show that features have evolved in populations over time. It is not necessary to show the change in these features in a direct ancestral line.

Look at it like this...

Imagine you were trying to find and catalogue a photo of each of your direct male relatives, father, grandfather, great-grandfather, etc, in order to compare a particular feature, say nose size. You have photos that span 10 generations (unlikely, but humour me) but you are missing one photo, lets say the 7th generation. As luck would have it, you do have a photo of the brother of your missing direct male relative. Of course you would prefer to have the actual direct relative, but in the absence of this photo, the photo of the brother can still act as a good substitute. It is likely that the brother had similar features to your direct relative and so his nose size is still informative. In fact you could look at photos of siblings for a few of the generations and not really lose any informational power. This is why transitional fossils, or features, do not need to come from a direct ancestor.

Anyway, the demands of creationists in this respect are ludicrous. Even if there were fossils in a direct ancestral line in front of them, they would simply say that there still isn't enough evidence. They would ask for the fossils that show transition from each specimen to the next (i.e. imagine a photo with twice as many skulls). If you could provide them, they would ask for the next set of intermediate fossils, and again, and again...

More fossils to a creationist doesn't mean more evidence, it means more gaps! It seems like the only way to satisfy them would be to produce fossils from every organism that has ever lived on this planet.

Meh.

------------------------------------------------------------------

Edit: Below is the chart showing that although creationists are adamant that none of these are transitional and all are either apes or humans, they are not able to agree on which are which.

Evolutionists also disagree on how fossils should be classified, which species they belong to, etc. True enough. But according to evolutionary thinking, these fossils come from a number of closely related species intermediate between apes and humans. If this is so, we would expect to find that some of them are hard to classify, and we do. Creationists, on the other hand, assert that apes and humans are separated by a wide gap. If this is true, deciding on which side of that gap individual fossils lie should be trivially easy. Clearly, that is not the case.



Uploaded with ImageShack.us

Hat tip to BathTub

16 comments:

Anonymous said...

Total made up bull shit! You're an intellectually dishonest moron.

rhiggs said...

Thank you Anonymous for your insightful comment.

Care to elaborate or do you just do unsubstantiated drive-by insults?

rhiggs said...

*cricket sounds*

Froggie said...

Rhiggs,
Very well done!

I hope to refer some folks here that are sorely in need of this information.

Take Care,

Frog

zilch said...

Anonymous: your witty yet intellectually devastating critique has convinced me! Glory Gee to Beezus!

rhiggs: nice work, as usual. Remember to look me up if you're ever in town.

rhiggs said...

Froggie, Zilch,

Cheers for the comments. Zilch, will defo look you up if I find myself in Vienna. If either of you are ever in Ireland, let me know.

All the best,

Rhiggs

Wester A Chincey said...

Excellent post. I have cited a number of people here. Rarely do you find a digestible counter proof to the "there are no transitional fossils" claim. Unless someone subscribes to anonymous' claim that perhaps you photoshopped a bunch of fake skulls or whatever he is trying to hold onto, this is hard evidence to ignore, even for those who don't have a good grasp over evolution. I suppose some poor saps will still cling to what they believed before, but I'd hope this would get others to consider that maybe science isn't a bunch of rubbish.

rhiggs said...

Wester,

Welcome.

Thanks for your comment.

It's interesting that you and I are forced to speculate as to what Anonymous' quibble with my post is.

My guess is that your photoshop suggestion is far too sophisticated. He/she probably just looked up 'transitional fossils' in the bible, found no reference and, ahem, 'reasoned' from there...

Anonymous said...

Nice post, but this is just a very small part of the larger picture. You are simply talking about transitional fossils within the hominid tree. There's quite a leap to take from inert proteins to intelligent life. As a christian and a scientist, I certainly can't exclude the possibility that these theories are correct, but they are flimsly by true scientific standards when taken into a larger context. I'm continually amazed at the dogmatic arrogance of evolutionists. Scientific theories continually change and, if history continues to be correct, what we think now will seem ludicrous in a few hundred years.

rhiggs said...

Anonymous,

Nice post,

Thank you.


but this is just a very small part of the larger picture.

Agreed.


You are simply talking about transitional fossils within the hominid tree.

Agreed. But I could have done a similar post about transitional fossils between many other species. Human origins are just that bit more interesting.


There's quite a leap to take from inert proteins to intelligent life.

Agreed. This article doesn't discuss that but it's an interesting topic.


As a christian and a scientist, I certainly can't exclude the possibility that these theories are correct, but they are flimsly by true scientific standards when taken into a larger context.

I disagree. Evidence for particular transitions may be flimsy, but the state of the overall theory of species-to-species transition is very solid. The evidence from paleontology, geographical distributions studies and genetics is overwhelming.


I'm continually amazed at the dogmatic arrogance of evolutionists.

No dogma, just evidence. The sad thing is, I'm continually not amazed at the dogmatic arrogance of creationists


Scientific theories continually change and, if history continues to be correct, what we think now will seem ludicrous in a few hundred years.

Maybe. But at least science is self-renewing, unlike Christianity which is dogmatic.


Thanks for your post

Anonymous said...

You forgot to include the skull of the Piltdown man. OH ,I forgot that skull was found to be a forgery made up from human skull with an orang-outang jaw and chimp teeth which was the standard for evolutionists for 50 years before being discovered as a fraud. The basic genetic code for each species stays the same. Show me the transitional fossil from monkey to man. Make another Piltdown man if you wish...

rhiggs said...

Anonymous (III),

What a completely ignorant comment. No wonder you wish to hide your identity. Let's take each ridiculous sentence at a time...


"You forgot to include the skull of the Piltdown man."

No, I didn't 'forget to include' it. Its not there because it doesn't belong there.




"OH ,I forgot that skull was found to be a forgery made up from human skull with an orang-outang jaw and chimp teeth..."

Exactly. You forgot it was a fraud. That's not my problem. It's yours.



*still searching for a point*




"...which was the standard for evolutionists for 50 years before being discovered as a fraud."

Let me finish that sentence properly...

"...which was the standard for evolutionists for 50 years before being discovered as a fraud by evolutionists."

From Wiki:

In November 1953, The Times published evidence gathered variously by Kenneth Page Oakley, Sir Wilfrid Edward Le Gros Clark and Joseph Weiner proving that the Piltdown Man was a forgery and demonstrating that the fossil was a composite of three distinct species.

Guess who those guys were? They were scientists. That's the good thing about science. It is self-correcting, unlike religion. Just because one guy back in 1912 decided to make up a fraudulent skull has no implications on the validity of evolution and common descent.




"The basic genetic code for each species stays the same."

Sure the basic code remains the same (although there is some minor variability). Did you have a point? Just because the code is the same makes no difference to the variability in the sequence, which is what is important. Your 'argument' is like saying someone copying a manuscript can't change it through errors because its still in the same language.




"Show me the transitional fossil from monkey to man."

No I won't because man didn't evolve from monkeys!!!. Go and learn something about the subject you are hopelessly trying to attack. The above picture shows transitional fossils between early hominids and man, with a modern chimpanzee skull for comparison. Just a few weeks ago, even older fossils than the above ones have been found bringing us even closer to the common ancestor between humans and other apes.

BTW if you want to see the fossil of a possible common ancestor between man and other primates look here.




"Make another Piltdown man if you wish..."

Why would I wish to do that?

Let me get this straight. You have no argument at all so you are bringing up a fraudulent skull from a century ago, that I didn't include in my post, to somehow try and accuse me of being wrong. You are a complete moron. If that is the best you have I suggest you go back and re-sit your Creationist Arguments 101 exams because you were clearly bottom of the class.

BathTub said...

Yeah it is a great image, and what's funny is that it's out of date now. There are 2 more to add to it. Ardi and Sediba.

rhiggs said...

I just posted this comment here in response to a criticism of this post at the Premier forums by Ploughboy:


"Homo ergaster, H. erectus, H. neanderthalensis, H. heidelbergensis and H. sapiens are all modern man, the rest are apes."

OK, so you are saying that skull A-F are all apes and skulls G-N are modern man (see here for better version of the image). So despite the wide range of differences between skulls A-F and the wide range of differences between skulls G-N, your issue is solely that there is a huge insurmountable difference between skull F and skull G. Correct? If so, this is clearly, well, ridiculous.

Just to scratch the surface...

It is obvious (to any intellectually honest person) that the difference between skull F and skull G is far less than the difference between skull A and skull G - just compare the cranial size, the positioning of the eye sockets and the flattening of the maxilla. What you are forced to concede (if you are honest) is that, by your own labelling, this means an ape skull and a modern human skull (F and G) are much more similar than two ape skulls (F and A). Surely this shouldn't be the case if apes and humans are completely separate and distinct from one another. Ape skulls should be ape skulls and human skulls should be human skulls.

Furthermore, Skull A is that of a modern day chimpanzee, which has the closest resemblance to a human skull of any living ape. It is clearly very different even to Skull B. The positioning of the eye sockets is very much lower - but wait! - this time the cranial size and the flattening of the maxilla are not that different. That is bizarre? Almost seems, erm, what's the word I'm looking for? Ah yes - transitional. In fact, it could be argued that Skulls B-F, which you claim are apes, are all more similar to Skull G, apparently a modern human, than a modern chimp skull.

You claim that Skull G is that of a modern man. The first thing you should notice is the vastly reduced cranium compared to Skull N. No modern humans have skulls like this. Next, look closely at the teeth. You can see the incisors protrude out and are very big and sharp, while the rest are much bigger than human teeth. Many humans have bad dental hygiene but I can guarantee you that none have teeth like Skull G.

I don't expect you to be convinced because you have clearly made up your mind already. It is worth exposing how silly your argument is though. But don't worry, most creationists can't even agree on which skulls are apes and which are humans (as documented here). This is exactly what we would expect from evolution as the boundaries between each species are somewhat blurry and simply based on the fossils we find. Indeed, all organisms - even you - are transitional forms.

BathTub said...

I was going to say here is the table in image form.

http://img55.imageshack.us/i/creationistconfusionsy5.jpg/

but I see a new column has been added to it since that image was made.

It needs to be updated again. AIG things Sediba was fully human and Aferensis is fully ape. It keeps getting better and better.

rhiggs said...

@BathTub

Great thanks. I'll add it in as an edit.