Sunday, May 31, 2009

Bad Reason #4 – There are no transitional fossils

This is the fourth article in my series of 10 bad reasons to reject evolution, this post deals with the objection that "There are no fossils that show transitions between species".

Of all the bad reasons to reject evolution this one is probably the easiest to deal with, that's because it's demonstrably wrong. A transitional fossil is one that is usually supposed to show a transition between one type of animal and another. Looking at this from a species point of view it would seem difficult to spot the differences between say a Herring gull and a Lesser Black backed gull fossil although we know they represent two different species, one may be a bit smaller for example but without the genetic differences physiologically pretty similar. What people usually think of when we say "transitional fossil" is more along the lines of something that shows evidence of the relatedness of all living things, for example a transition between fish and reptiles or dinosaurs and birds or snakes and lizards, some fossil that shows an animal somewhere on the path between the two groups, so a raptor with feathers or a fish with legs etc.

Interestingly we have great examples of all of these transitions, some famous fossils like Archaeopteryx show dinosaur-bird transition but others, perhaps less famous, like Tiktaalik show the fish-land reptile transition among many others, here is a list of some of the more well known ones, Google the names to see pictures and to read about them in more detail.

Archaeopteryx – Has a wishbone and feathers like a bird but a long bony tail, teeth and fingers like a dinosaur.

Sinornis – A bird with bony fingers and teeth

Yinlong – A small bipedal dinosaur with a beak

Bohlinia – A giraffe with a "medium" sized neck (most older fossils show giraffes with short necks)

Pezosiren portelli – A Manatee with legs, showing a transition from hippo like land animals to the sea dwelling manatee

Moeritherium – A small hippo like mastodon with tusks but no trunk.

Dimetrodon – A sail backed dinosaur with a skull and teeth physiology that only mammals have.

Tiktaalik – A transition between fish and land animals, fish like fin rays and joints like land animals (also surprisingly an ear that could hear in and out of water)

Gerobatachus hottorni – shows the common origins of frogs and salamanders

Osontochelys semistestacea – An animal on its way to becoming a turtle with half a shell and teeth (unlike modern turtles)

Ambulocetus - An amphibious mammal on its way to becoming a whale.

Most recently of course we have Darwinius masillae or "Ida which shows the transition between early primates and more recent forms like humans. As I have said before the concept of a "transitional" creature is somewhat of a misnomer, all creatures are transitional between what came before them and what will come next, a sobering thought.


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