Answering Creationist Claims - (Part 2b - No Intermediates? Wake Up, Please.)

Ignorant of the theory of evolution, Bible Life Ministries goes on to claim that all fossils doesn’t represent intermediates; those that do are frauds. Funny how creationists would refuse to consider all those verified fossils and instead claim that the Paluxy River footprints are proof of creation. Without wasting time, let’s take a look at their claims.

Ardipithecus ramidus

Probable life appearance in anterior view of Ardipithecus ramidus.

The find for “Ardi” began in 1994, in the Middle Awash region of Ethiopia. Dated at 4.4 million years ago. Ardi further completes our understanding of human evolution. Such a fossil would certainly be picked apart by creationists with the “greatest” claim ever: “It’s just an ape.” Not an average ape, mind you.

By bringing us closer to the 6,000,000 BC point in which humans-to-be and chimpanzees-to-be diverged, Ardipithecus revolutionised the way we think of our ancestry. It weakened the theory that protohumans were savannah apes that diverged from a quadrupedal ape. Instead, Ardi was a fully bipedal, woodland ape.

What Makes "Ardi" a Great Fossil?

Feet Unlike Chimp's and Human’s

Ardi’s feet is quite intermediate between those of humans and those of chimps. Just like chimps, the toes are opposable, but they’re shorter. Plus, the feet aren’t flexible enough to from climbing trees and grasping veins, and they’re more human-like from that point of view.

Human-like Hands

The fingers of Ardipithecus ramidus are long and dexterous, much like human’s. Its wrists are also more flexible than those of contemporary apes.

Small Canines

Canines are used by apes as a sign of male superiority. In a monogamous society, male apes have large canines, and they’re used in conflict with other males when fighting over females. However, Ardipithecus ramidus fossils showed that males did not have large canines, and certainly not larger than those of females. This feature shows that our ancestors did not have much conflict between males and males, and is great evidence that our ape ancestors had more pair-bonding and parental investment than previously thought.

Pelvis Suited for Walking

Ardi’s pelvis, although crushed and needed to be reconstructed by advanced digital technology plus anatomy experts, it nevertheless points to the fact that Ardi’s pelvis are wider than quadrupedal chimps and narrower than bipedal Australopithecines aka intermediate. This is greater evidence that our ancestors became bipeds before geniuses (Ardi’s brain volume is estimated to be 300 and 350 cm³, which is about the size of a modern bonobo’s/female chimp’s brain, but smaller than Lucy's 400 to 550 cm³ brain).

Archaeopteryx

Archaeopteryx Fossil (Berlin)

Archaeopteryx – arguably the most famous fossil ever. Found in a limestone quarry in Southern Germany in 1861, the bird is now widely recognised as the best example of the reptile-bird transition. And guess what, Bible Life Ministries call it a fraud. They claim that it is a dinosaur fossil with fake feathers, and thus shows how dishonest evolutionists are.

OK, so the source came from In the Beginning: Compelling Evidence for Creation and the Flood, written by Dr. Walt Brown, who isn’t a scientist. Here’s the quote: “Allegedly, thin layers of cement were spread on two fossils of a chicken-size dinosaur, called Compsognathus. Bird feathers were then imprinted into the wet cement”. It’s on page 148.

Unfortunately, the case doesn’t hold strong for Bible Life Ministries. Palaeontologists that examined the London Archaeopteryx arrived at a quite different conclusion - “Proof of authenticity is provided by exactly matching hairline cracks and dendrites on the feathered areas of the opposing slabs, which show the absence of the artificial cement layer into which modern feathers could have been pressed by a forger.”. This is featured here: Archaeopteryx is not a forgery..

To add to the point, Compsognathus’s skeleton is much more different from those of Archaeopteryx – there are too much differences between the 2 species. In fact, there could not have been a better reptile-bird intermediate. I shall not reinvent the wheel, as there is already a good source here: Archaeopteryx's Relationship With Modern Birds

Titaalik roseae

One the most beautiful discoveries in the early 21st century would be Titaalik. Found in 2004 by Neil Shubin and his team in the Arctic Circle, it is now in the Hall of Fame as one of the most important fossils, well alongside Archaeopteryx and Australopithecus. Tiktaalik is the perfect example of the fish-tetrapod transition. Once again, Bible Life Ministries claim it is a fraud.

Tiktaalik Model with Fossil Cast

Here’s their funny argument: “Since Archaeopteryx is a fraud (of course it’s not), therefore Tiktaalik is a fraud!” Don’t understand their logic? Me too. Unlike Piltdown Man, Archaeoraptor, and other frauds, Tiktaalik was certainly not found by “amateurs”, and the process of finding and excavating it is quite well documented. Bible Life Ministries, perhaps you would be kind enough to read “Your Inner Fish” by Neil Shubin?

Yet in a twist, Bible Life Ministries suddenly change their mind and acknowledge that Tiktaalik is true, just not an intermediate - it is nothing more than another species of fish. Notwithstanding the confusion, let us show the poor (wilfully ignorant) creationists why is Tiktaalik so exciting, and how it contributes to a better understanding of evolution.

What Features of Tiktaalik Make It a Fish-Tetrapod Intermediate?

Loss of the Operculum

The operculum is a plate of bone that forms a flap that covers the gills in most bony fishes. The operculum’s primary function is to assist the fish in moving water across the gills. Losing the operculum allows the neck to move freely. All tetrapods don’t have the operculum, while primitives ones still retain the gill but have lost their operculum nevertheless. Tiktaalik lost its operculum but retained the gill, which is only expected from a fish-tetrapod intermediate. By losing the operculum, Tiktaalik was able to move its head independent of its body, and had a true neck. Also, without the operculum, Tiktaalik should’ve breath mainly using its mouth.

Dwarfing of the Hyomandibula

The stapes is a piece of bone in our middle ear. It was originally a gill arch bone known as the hyomandibula. In Eusthenopteron, the hyomandibula large and boomerang like, in Acanthostega it's a small piece of bone, and in Tiktaalik it's exactly between.

Comparison between the operculum and hyomandibula of fish and tetrapods.

The Skull

The main difference between fishes and tetrapods is the shape of their skull. Fishes have round, conical skulls with their eyes on the sides; tetrapods have flat skulls with their eyes on top. Tiktaalik has a flat skull, yet with some leftover characteristics from fish skulls.

Dorsal view of Tiktaalik skull. Scale bar equals 5 cm.

Primitive Wrist Bones and Fingers

Fishes have fins, tetrapods have limbs. This is one of the main differences between them. To crawl on land, the fins are expected to evolve into limbs. And that’s what seen in Tiktaalik.

The difference between fins and limbs lie mainly in their skeletal layout, The base of a typical fin contains 4 or more pieces of bones; limbs have a single bone known as the humerus that connects to the shoulder, which are connected to 2 forearm bones, then to pieces of bones, and finally to digits.

So let’s take a look at Tiktaalik’s fin/limb. One can only awe at what a great finding it is indeed – to have found such a perfect intermediate between swimming fins and walking limbs. Read the description, and see for yourself.

a, Dorsal view; b, ventral view. Elements with stipple shading were preserved in articulation in NUFV 109 and prepared in the round. Elements with a dashed outline are reconstructed based on their presence in the articulated distal fin of NUFV 110. It is not known how many radials lie distal to the first, second and fourth in the proximal series. Note the dorsal expansion of the distal articular facets on the ulnae and third distal radial/mesomere. The dorsal expansion of these facets would have facilitated extension of the distal fin.

Other Claims

Here’s a list of species which are obviously unrelated to transitional fossils, yet somehow included by Bible Life Ministries in their unfounded claims.

The Coelacanth

A living fossil.

Once thought extinct since 70 million years ago, the coelacanth was found in December, 1938 off the eastern coast of South Africa. Quite a startling discovery indeed, as it is such a great “living fossil”. That is, not counting the opportunity that the coelacanth provided for creationists to annoy us.

So it basically boils down to the same old question: “Since the coelacanth has remained unchanged for 350 million years, evolution is false.” This assumption is so wrong on many levels.

Firstly, this thought wrongly assumes that evolution is linear, continuously progressing towards humans as an end product. Instead, evolution is continuously branching, a process known as speciation. A fish can keep on evolving into a better fish while another fish may evolve to survive on the land. The coelacanth is one that stayed in water.

It is also wrong to think that evolution is working towards a goal with an end product in mind. It is driven by the force of natural selection, that is the continuous interaction between individuals in a struggle to survive and reproduce. Our ancestors did not have a great plan to live on land, it was just natural instinct for survival that led them to venture out of water, perhaps to escape larger, predatory fishes. The coelacanth is a fish that managed to survive in its current form, and thus did not need to change.

Lastly, the living coelacanths represents the genus Latimeria, not a species, and has changed from its ancestors. It is just that the changes were minor.

The Platypus

Evolution: Results may vary.

I’m not very sure what exactly is Bible Life Ministries is trying to prove by using the platypus, but I’ll address it nevertheless.The platypus and the echidna are monotremes, the only mammals that lay eggs, and the platypus sure seems to have quite mix of mammalian and reptilian features (At least Bible Life Ministries is right on this one). What I find funny comes next.

Bible Life Ministries then goes on to claim that the platypus has the characteristics of many creatures but is not a link to any of them. Duh!!! No one ever said that the platypus was a link to any species! Mammals diverged into 2 different branches about 140 million years ago, one of them which would later diverge into placentals and marsupials; the other branch consists of the monotremes. Get your facts straight.

But what about the supposed “mix” of the characteristics in the platypus? Well the platypus is halfway between mammals and reptiles, so no surprise that it moves quite awkwardly. It lays eggs because it works, so no reason to change it. The males have poison as a result of sexual selection, and it doesn’t kill, just create great pain. Its famous bill is simply convergent evolution, and works quite differently from a duckbill. No problem for evolution whatsoever.

An Atavistic Dolphin

An atavistic dolphin was caught in November 2006.

It seems here that Bible Life Ministries thought that we actually labelled the dolphin with rear flippers as evidence that dolphins evolved from dogs. Please, creationists, the article itself stated that it was a dog-like ancestor, not dogs. Sheesh. Moreover, Bible Life Ministries last sentence stated that the dolphin was just another odd species that “god” created. That shows their complete misunderstanding of what the fuss was all about.

What we find fascinating here is not that we found a vestigial flipper. It is long known that cetaceans’ hind limbs are hidden within their body (See my previous post for more details). Instead, what we are dealing with here is an atavism, which is the appearance of a structure that was present it the individual’s ancestor, but not anymore in the present. In other words, it means that hind limbs of mammals were once present, but have since been reduced to pieces of bone in the dolphins body; this bottleneck dolphin however has hind limbs, and thus is a case of atavism. Another example is the growth of toes in atavistic horses. Atavisms are caused by a abnormal reading of genes, in which pseudogenes are accidently transcribed.

Conclusion

It certainly looks as if Bible Life Ministries did not do any research on the transitional fossils listed. They're just repeating the mantra: "There're no transitional fossils... Just show me one, just one...". It it shown in this post that there are quite a large number of transitional fossils, despite the fact that this is just a tip of the iceberg. No more excuses, creationists. Face the fossil record.

Bible Life Ministries 3rd claim focuses on missing evolutionary branches. However, this claim isn’t even an argument, but simply a gross misunderstanding of the Theory of Evolution. I’ll explain it in the next post.

References

Shubin, N.H. (2009) Your Inner Fish. Penguin Books. ISBN 978-0-141-02758-6

Daeschler, E.B. et al. 2006. A Devonian tetrapod-like fish and the evolution of the tetrapod body plan. Nature 440: 757-763.

Charig et al, Archaeopteryx is not a forgery., Science, 1986, v.232, p.622-626.

Previous: Answering Creationist Claims (Part 2a - We Don't Jumble Fossils Together)

Next: Answering Creationist Claims (Part 3 – What’s a Missing Inferior Branch?)

Answering Creationist Claims (Part 1 - Birds Support Evolution)

“One of the best examples of evolution nonsense is the thought that a wingless bird began to evolve a wing. Why this would occur is not answered by evolutionists. The wing stub did not make the bird more adaptable to his environment. The first wing stubs would be much too small for the bird to fly. Why would a bird evolve wing stubs that are useless?…A bird with a useless wing is at a severe disadvantage…

…We are then led to believe that some birds got tired of carrying around a worthless half-size wing, so they grew fingers on the end to help climb trees. The wings became arms and a new species was developed.”

So here’s the first claim. Birds could not have evolved their wings, since a wing stub would've been useless. The creationist tries to tell us that a wing could not have evolved through evolution, for what is the use of half a wing? Yet this attempt is simply laughable.

Bird Wings came from Dinosaur Arms

The creationist makes 2 serious mistakes in the claim above. Wings did not evolve from wing stubs, and they did not evolve in to arms. They evolved from arms. According to current evidence, birds evolved from small theropods. This can be shown through the many similarities between the physiology and behaviours of birds & dinosaurs. In fact, the current fossil evidence shows quite a smooth transition from theropods to archaic birds to modern birds. Molecular evidence also puts crocodiles to be more closely related to birds than they are to lizards, turtles, snakes and other reptiles, which strongly supports the theory that birds evolved from dinosaurs, since dinosaurs and crocodiles share a common ancestor known as archosaurs. The wings of birds are evolved theropod arms.

From left to right: Compsognathus, Archaeopteryx, Gallus gallus(chicken).


From left to right: Deinonychus Hand, Archaeopteryx Hand


Birds are classified in the phylogenetic tree as dinosaurs.

OK, so we have now established that birds did evolve from dinosaurs. However, the creationist puts may ask: “But still, what is the use of a something halfway between a wing and an arm?” Don’t worry. Science has its answers.

Flight involves 4 physical forces (thrust and drag, lift and weight). For a bird to fly, many characteristics are required: feathers (improve aerodynamics), wings (create lift), hollow bones (increase structural strength), beaks replacing jaws (reduce weight) and so on. At first glance, this may give the look that since non-fully developed characteristics would've been useless, the Theory of Evolution has been determined false. It's not. Let's see how birds could've gained flight.

Flight evolutionary models

Archaeopteryx, the earliest and most primitive bird known.

The Cursorial Model

This model states that flight evolved in running bipeds through a series of short jumps. As the length of the jumps extended, the wings were not only used for thrust but also for stability, and eventually eliminated the gliding intermediate. The model was then modified to describe the use of wings as an insect foraging mechanism which then evolved into a wing stroke. By running then jumping, less energy would've been used compared to only running. Combined with Archaeopteryx’s long and erect legs, supporters say that birds gained flight through jumping from the ground.

However, although this model sounds plausible, current evidence refutes it. Due to its weight, Archaeopteryx would need to run faster than birds by a factor of 3 to fly! Also, the heavier the bird, the longer it needs to run. For Archaeopteryx to fly, just guess how much energy it has to waste! Archaeopteryx’s ineffective aerodynamics also means that it could only fly for extremely limited times before falling! Thus, physics strongly disagree with this theory.

The Arboreal Model

The model states that Archaeopteryx was a reptilian bird that glided from tree to tree. After the leap, Archaeopteryx would then use its wings as a balancing mechanism. Archaeopteryx developed gliding to save energy according to the model. Although climbing trees may sound energy-wasting, the benefits are great. By gliding from tree to tree, Archaeopteryx would've conserved a lot more energy than staying on ground.

This model is supported by the fact that Archaeopteryx’s foot claws and hallux are very similar to those of modern perching(standing on branches) birds. This characteristics strongly support the view that Archaeopteryx was arboreal. Current tests have also shown that despite not having a supracoracoideus pulley system (SC), Archaeopteryx can still glide jumping from trees. It would've not been able to fly by running though.

However, a study suggested that the arboreal and cursorial model are not mutually exclusive, as many extant birds exhibit different degrees of ground- and tree-based behaviours. Instead, the study proposed that birds should be placed on a spectrum according to the extent of ground and/or tree foraging they exhibit.

The Pouncing Proavis Model

This hypothesis was first proposed by Garner, Taylor, and Thomas in 1999. This hypothesis is distinct from the hypotheses above in that it “proposes that locomotor control, rather than some direct attribute of flight such as speed or efficiency, was the selective pressure that initiated the evolution of fight in birds”. This hypothesis makes the claim that birds evolved from small predators that ambushed their prey from elevated positions. Over time, natural selection would favour those predators that had greater lift-based control, slowing turning the action from pouncing into swooping. Further selections for greater swooping ranges will then lead to flight.

The authors believed that this model is superior the previous models for these reasons:

The Mosaical evolution of Archaeopteryx

Both of the models are unable to explain why Archaeopteryx has a theropod-like skeleton and yet has a fully feathered wing, as they predict the co-evolution of the whole suite of skeletal and non-skeletal flight characteristics in birds. On the other hand, the Pouncing Proavis Model predicts the evolution of an Archaeopteryx-like grade of organization through continued selection for enhanced control of body position during a jump or controlled fall.

The Coexistence of Primitive Pouncers and More Advanced Fliers

Fossils of feathered dinosaurs were found in Late Jurassic and Early Cretaceous deposits, such as Sinosauropteryx, Caudipteryx, and Protoarchaeopteryx. Rahonavis, a dromaeosaur with bird-like characteristics were even found in the late Cretaceous! On the other hand, archaic birds such as Iberomesornis were found at the same period. This means that bird-like-dinosaurs and birds coexisted.

The arboreal and cursorial model predicts that as theropods became more adapted to flight, natural selection will eliminate theropods that did not show such abilities. But this is not the case. In contrast, the Pouncing Proavis Model predicts animals that started evolving Archaeopteryx-like features would have been selected for flight control instead of speed and agility. Gradually, however, natural selection pressures would begin selecting for improved flight efficiency, allowing those theropods to develop into a more bird-like niche. As pouncing bird-like dinosaurs and fully developed birds would not compete directly, they can coexist, and this matches the fossil record.

The primitive perfection of feathers

Both the arboreal and cursorial models proposes that feathers evolved under natural selection for increased life. However, it is hard to see how any feathers more primitive than modern feathers can generate enough lift. Instead, the Pouncing Proavis Model proposes that feathers were initially selected for increased drag, not lift, as this model proposes that the initial selection was for improved control during pouncing/swooping. Through continuous selection for increased drag and improved structural stability, feathers suitable for flight would evolve. This process of getting entirely new functions from existing systems is known as pre-adaptation.

Diagram showing the stages of feather evolution as outlined by Xu & Gou 2009.

Successful Prediction of the Theropod-Bird Transition

The Pouncing Proavis model is consistent with the current evidence, whereas the arboreal and cursorial model are not. This model matches the currently observed sequences of character acquisition by theropods. For example, the Pouncing Proavis Model and the cursorial Model successfully predicts that Archaeopteryx is ground-dwelling; while the arboreal Model fails to do so. On the other hand, the arboreal and cursorial models proposes wrongly that weight reduction evolved parallel to an improvement in wing aerodynamics; however, the fact is that birds reduced weight after that, and the Pouncing Proavis model predicted is consistent with this finding.

Wing-assisted Running(WAIR) Model

Wing-assisted running is a recently discovered locomotor behaviour that allows birds to ‘run’ up obstacles(Dial, 2003). While such a task seems formidable for a biped, WAIR is used by ground-dwelling birds to escape from danger. Instead of supplying thrust in the direction of travel and lift to support body weight, the WAIR hypothesis suggests that the wings of ground birds serve to increase hind limb function and push the bird towards the substrate(the place they are running on), increasing traction. This is achieved through the simultaneous flapping of wings and running. The WAIR model have been documented in up to 4 species of ground birds.

So how does this explain the evolution of flight? When escaping from predators(perhaps when chasing prey?), protobirds that are able to use WAIR will have much higher odds of survival compared to ‘normal’ theropods, as they can reach elevated positions(cliffs, hills, trees, etc.) For protobirds to achieve this feat, the wing doesn’t need to be very big, but feathers are required. 3-day old hatchlings were documented to use their partial wings the run up steep inclines, while those with feathers removed could not.

There has been however research that disagrees with WAIR. It was found that the shoulder joint orientation in protobirds prevented the lifting of of the wing higher than the backbone, thus preventing flapping flight, and WAIR as well. (Senter, P. 2006)

Despite the importance of such a hypothesis in explaining the evolution of flight in birds, much remains unknown about the mechanics of WAIR, and work still needs to be done.

Could this be how birds conquered the sky?

Conclusion

We have now refuted the creationist claim that birds cannot be evolved from earlier, transitional forms:

“The idea that birds or anything else has million-generation evolutionary plans is childish. The evolutionary concept of growing a wing over millions of generations violates the very foundation of evolution, natural selection.”

You’ll need to try harder, evolution-deniers.

But that's not all! In the same topic, further claims are made that no species are able to evolve into another species, aka fish-to-amphibian, amphibian-to-reptile, archosaurs-to-dinosaurs….. (with added insults). This is a common creationist claim, and I shall address it in the next post: Missing links? Wake up, creationists.

PS: There is this claim about how Cetiosaurus’s long neck disprove evolution. I would like to address this, but it’s not important in this series. Perhaps I will give a answer after this series.

References:

Glen, C.L., and Bennett, M.B. (November 2007) (abstract page). Foraging modes of Mesozoic birds and non-avian theropods. 17.

Garner, J., G. Taylor, and A. Thomas. 1999. “On the origins of birds: the sequence of character acquisition in the evolution of avian flight.” The Royal Society. 266, 1259-1266.

Xu, X. and Guo, Y. (2009). The origin and early evolution of feathers: insights from recent paleontological and neontological data. Vertebrata PalAsiatica 47 (4): 311-329.

Matthew W. Bundle and Kenneth P. Dial. 2003. "Mechanics of wing-assisted incline running (WAIR).” The Journal of Experimental Biology. 206, 4553-4564"

Senter, P. 2006. Scapular orientation in theropods and basal birds, and the origin of flapping flight. Acta Palaeontologica Polonica 51 (2): 305–313.

Previous: Answering Creationist Claims (Introduction)

Next: Answering Creationist Claims (Part 2a: We Don’t Jumble Fossils Together)