Sunday, May 31, 2009

Bad Reason #3 – We haven’t got all the fossils

This is the third article in my series of 10 bad reasons to reject evolution, this post deals with the objection that "We haven't got every single fossil going back to the first bacteria".

Here is another indicator of ignorance, both of the scientific method and evolution itself, it is quite common for non-scientists to think that in order to "prove" something to yourself you need to actually witness it, clearly this is a childish notion, reminiscent of a playground taunt "how do you know its true, did YOU see it?" etc. To illustrate the fallacy I could say that I've never seen Tokyo, but I'm pretty sure it exits.

Another misconception here is that the credibility of the theory of evolution rests solely on fossil evidence, this is not the case, and in fact most scientists would say that the DNA evidence alone would be sufficient. Having said that though I'm going to focus on fossils because that's the main focus of the objection, the fact that DNA and distribution evidence stand on their own and yet still support the fossil evidence simply adds overwhelming weight to the accuracy of the theory.

We are fortunate that we do have millions of fossils to look at, I say fortunate because fossilisation is an incredibly rare event. If we look at the world today an important question raises its head, that is, where are all the bodies? Our planet should be littered with dead bodies, millions upon millions of animals die every day and yet our gutters don't run with dead pigeons, squirrels, bacteria, foxes or carp, it is incredibly rare that we see dead animals in comparison to how common it is to see live animals. Clearly dead bodies are eaten. There is a whole eco-system of creatures that vacuum up the dead at every level of the food chain, from scavenging bird and mammal species such as crows and foxes down through insects such as beetles on to bacteria and fungi, all generating a fine living from dining on the dead. To create a fossil a very special set of circumstances needs to occur, primarily that the dead body is quickly taken out of the food chain (for example it is buried in mud), oxygen and bacteria cannot be present (perhaps at a dark, cold lake bottom) then the cells in the body need time to take up the minerals of the surrounding materials and eventually be transformed into sedimentary rock, this takes ages during which time the body cannot be disturbed, then the simple bit is that someone has to actually find it!

So is it really surprising that we don't see every fossil and more importantly why are the fossils we do have sufficient?

Looking at fossils is a bit like solving a crime by looking at a crime scene, only some of the evidence is available and what little is there needs to be matched up to the environment, the landscape and the timeline in order to prove beyond reasonable doubt that something has happened. If we only agreed to convict criminals if we could see every piece of evidence, i.e. a video recording of the actual crime then we wouldn't get very far, proof is about weight of evidence and not absolutes.

So where have we found good sequences of fossils that show beyond reasonable doubt that evolution and speciation has occurred, a good example would be the transition from land to sea in the case of the whales although there are many others. The key to discovering this set of transitions was finding where to look; apparently whales did a lot of evolving in what is now Pakistan, once this discovery had been made the floodgates of great whale fossil finds was opened and a very clear picture has emerged. In fact if you look at the skeleton of whales alive today there are some very big clues regarding their evolutionary heritage, the remnants of hind limbs can still clearly be seen, begging the question for the doubters why on earth would whales have back legs?

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