Thursday, 19 June 2014

Understanding creationism: An insider’s guide by a former young-Earth creationist - 4

Former YEC David MacMillan's fourth instalment in his series on how YECs mishandle the evidence for evolution is up at Panda's Thumb. The subject? Transitional fossils:
Young-earth creationists believe that all life, living and fossil, can be grouped into a series of families – they call them baramins, a made-up Hebrew word for “created kinds” – which all existed together at the same time from the very beginning. They use this completely artificial understanding of our planet’s biosphere in generating their concept of a “missing link”: in order for something to be a “true” transitional form under their model, it would have to be something halfway between two separate created “kinds”. Because they automatically assign every species to a particular created kind and only to that created kind, their “transitional form” is something that could never exist. 
The usual parodies of evolutionary transitional fossils, like Ray Comfort’s infamous crocoduck, are openly tongue-in-cheek. But because creationists see all animals as belonging to individual, immutable kinds, they represent evolution as “change from one ‘kind’ to another” claiming that evolution predicts we should see transitions between their “created kinds”: for example, a fossil that is midway between a dog and a cat. Just as with living species, all fossil species are placed within strict “created kinds”, allowing creationists to maintain the illusion that nothing is ever “in-between”. 
This characterization is a complete misunderstanding of what evolution actually predicts. No one expects one existing species to evolve into another. The “kinds” alleged by creationism simply do not exist in the evolutionary model; there is no line between one family and another that a transitional form needs to straddle. 
What creationists don’t recognize is that the theory of evolution does not predict “transitional” fossils at all – at least, not in the way creationists expect. Evolutionary theory does not predict that there will be “normal” fossils most of the time, while chimaera-like “transitional” fossils will appear tucked in-between. Evolution has no general prediction about a unique class of transitional fossils. Instead, evolution makes predictions about the specific morphology, age, and location of the individual fossils it expects to discover. It bases these individual predictions on other specific fossils that have already been discovered.When morphology and a variety of other factors indicate that one particular species is the distant ancestor of another particular species, evolutionary principles can be used to predict the attributes of one or more intermediate species.
If science denialists could grasp one thing - that evolution is not a ladder but a tree - then much of the confusion over transitional fossils would abate. Full article here.