Evolution Myths Busted
Evolution is often attacked by people who, for whatever reason, cannot accept it. Attacking an idea is a good way of testing it ideas that are weakly founded will crumble and should be discarded, and ideas that pass through the attacks unscathed can be trusted a little more, their strength having been demonstrated. It is by this constant testing of ideas and rejecting those that fail that science itself can evolve and progress, filtering out the weak ideas and moving on to stronger ones.
Unfortunately, almost all of the attacks on evolution and the theory of evolution are actually attacks on a
misunderstood version of evolution that bears little resemblance to the reality.
Sure, this "straw man" version of evolution is easy to score points against, but since no-one actually thinks or argues that the straw man version is true, this is something of a pointless exercise, leaving the real evolution unscathed
In order to challenge evolution and evolutionary theory you first have to understand it, otherwise all you can really challenge is your own misunderstanding of it. I'm certainly no expert, but I have spent some time studying the basics, and I'd like to bust a few of the most common misconceptions about evolution.
Myth # 1: Transitional Forms
One of the most common misunderstandings about evolution concerns transitional forms. When scientists tell us that mankind's distant ancestors were fish, some people make the false assumption that there must therefore be evidence of some strange half-fish half-human creature along the way a kind of "missing link" resembling both the distant ancestor and the modern-day descendant.
This is not how evolution works. The false assumption here is the belief that evolution always proceeds along a straight path, for example: from A (the fish of the distant past) to Z (the human of today), and deducing, based on this misconception, that creature M, midway between A and Z, will always resemble some kind of hybrid of A and Z, and that as we move from A to Z our ancient fish will become steadily more human-like.
Evolution cannot see into the future it can't set a distant goal and work steadily towards it. Natural selection always selects what works best NOW. With countless environmental factors pulling in different directions at different times, the path evolution takes is rarely a straight one, at least for long!
The famous example of the "crocoduck", a strange and entirely fictitious half-duck half-crocodile creature, is a good example of related misunderstanding of evolution writ large.
Evolution tells us that modern birds, including ducks, and modern reptiles, including today's crocodiles,share a common ancestor.
The crocoduck is the result of a misunderstanding about what conclusions we can draw about that ancestor from the relationship between the two modern species.
Birds and crocodiles share a common ancestor - but that ancestor was
not a bird and was
not a crocodile.
The misunderstanding comes from the false assumption that the features of this
distant ancestor must therefore be a mix of the features of the two
modern descendants - the modern crocodile and the modern duck.
Evolution does not say that "once upon a time there was a crocoduck, and it had two children, one of which was a duck and the other was a crocodile". The above assumption fails to take into account the vast amount of time..the huge number of generations...between the ancestor and the two modern descendants - time in which both lineages have been gradually and independently changing - diverging along different paths, becoming
increasingly different not only from the common ancestor but also from each other.
Evolution lets us look back along those paths, into the deep mists of the ancient past, all the way back to the distant time where they join - the time when the common ancestor of modern ducks and modern crocodiles lived. What would evolution suggest this common ancestor have looked like?
First of all, unlike the crocoduck, it almost certainly didn't have feathers. These evolved much later than the time of the common ancestor, a long way down the path that happened to lead to modern birds. Expecting the distant common ancestor to have a combination of the features of its modern descendants is a little like expecting the Model T Ford to look like a combination of the Ford Mondeo and the Ford GT-90.
There will likely be some core features in common between the ancestor and the descendants, basic features that remained essential to functionality throughout the changes in the environment over time (such as eyes and wheels in these examples), but many of the features present in the modern examples simply didn't exist back in the ancestor's day.
It is possible for a common ancestor of two very different-looking modern species to closely resemble one of those modern species and not the other - part of the ancestor species' population could branch off into a different environmental niche (and over time become very different in appearance) while the rest stay where they were and change very little over the millennia (if there environmental niche remained largely unchanged, and there was no selection pressure from predators for example).
As it happens, the common ancestor of the crocodile and the duck would have looked a lot more like a crocodile than a duck, largely because it was been a quadrupedal reptile.
The line that lead from the common ancestor to the modern crocodile retained the quadrupedal stance over the millennia, whereas the line that lead from the common ancestor to the modern duck gradually evolved a bipedal stance, with the front limbs (now upper limbs) becoming first arms, and then wings, becoming birds. This line also evolved feathers, which greatly changed its appearance compared to the common ancestor, whereas the crocodile line remained featherless (although their scaled hide evolved over time too)
Evolution does
not lead us to expect the ridiculous half-and-half hybrids (combinations of two modern species) that opponents of evolution often mock it for.
Myth #2: Darwin's theory inspired the Nazi's evil eugenics / genocide
Eugenics is a form of
artificial selection an
intelligently directed process to achieve a particular purpose (a horrific purpose in the case of the Nazis).
Darwin's theory explains how species have changed over time
without the need for artificial selection - the core of Darwin's theory is
natural selection .
It is the
lack of a need for an intelligent director in Darwin's theory that made it so controversial it explains how complex life forms can arise from simple beginnings without an intelligent designer,
without any
artificial selection.
As such, Darwin's theory of
natural selection cannot reasonably be said to be the inspiration for the
artificial selection of Nazi eugenics. Artificial selection was known (and practised) by humans for many centuries before Darwin was born it is through artificial selection (selective breeding) that humans shaped dogs and farm animals to better suit human purposes.
Darwin's theory tells us that
in nature beneficial traits are more likely to be passed on to future generations than negative traits, due to
natural selection (I.e. Without any intelligent direction or conscious choice).
It does not tell us whether what happens in nature is morally good or bad Darwin's theory is amoral (not immoral!), just like Newton's theory of gravitation. It cannot be used to help us judge what is right or wrong, or to tell us how we
should behave, any more than Newton's Laws of Motion can tell us how we should behave (it tells us how we DO behave if we fall of a cliff, but it doesn't tell us that the falling is morally good or bad and couldn't reasonably be blamed if someone decided to throw others off cliffs).
Therefore anyone attempting to use Darwin's theories to morally justify genocide is fundamentally misunderstanding Darwin's theory and its scope they are misapplying biological principles onto the realms of ethics and politics. To jump from Darwin's "this happens in nature" to "therefore it is morally good" is to commit the naturalistic fallacy.
As it happens, Hitler made no mention of Darwin, but even if he had claimed to have been influenced by Darwin's theory it would have been his own
misunderstanding of Darwin's theory that lead him to his despicable genocide he would have been committing the naturalistic fallacy, and failing to understand that Darwin's theory is about
natural rather than
artificial selection.
There's many and relating to evolution, but I hope the above goes some way towards correcting those two particular oft-repeated misunderstandings.
The natural world is complex and beautiful, and all the more so as our understanding of it increases.
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