Friday, July 5, 2013

What Evolution Ain't

My original intention here was to start a series of blog posts about evolution from a layman's perspective.  In other words, I wasn't going to refresh my memory and give references, as my point was to simply write about it as best as I personally understood it.  This means that I'm bound to screw up, and I would hope that any of my friends who are more knowledgeable would comment and correct me.

Why write about evolution?  Because it is simultaneously one of the most amazing concepts in science, and yet it is one of the most misunderstood.  I'd like to say that that's solely the fault of religious fundamentalists, but I've heard people who supposedly accept the theory who still get some of the basic details of it wrong.  

Now that I've written all this, I'm not sure what I would write for a second entry, but I figure it's still a good starting point, as it clears up a lot of misconceptions.  I highly encourage everybody to not simply believe me though.  Look this stuff up for yourself, including from the "creationist" sites that supposedly have debunked it.  I know I looked at both sides quite a bit, only to reach the conclusion that there's actually only one side, and that's the one with the facts.

So, here's a bunch of stuff that people get incorrect, along with explanations as to why that stuff is bogus:

1.  Evolution is "just a theory".  Here's the thing, when science speaks about a "theory" the word does not mean the same thing as you or I do when we say something along the lines of, "I have a theory about why Michael Bolton was so popular."  In other words, it's not a guess that hasn't been proven.  It's an explanation for the evidence that we have.  To put things in perspective, gravity is still referred to as a "theory".  Yeah, it's a fact that if you drop something, it will fall, but the process which explains that phenomenon - gravity - is a theory.  Does that mean that it's open to debate?  Only in the sense that everything is open to debate in science.

The fact is that we have different species on this planet.  Another fact is that when we reproduce, we do not reproduce exact clones, and mutations can sometimes take effect.  It has also been observed that a species can produce another when the two populations separate and face different conditions.  Another fact is that there are many transitional fossils that show the progression of one species into another (look up whale and horse evolution).  Lastly, our DNA reveals that we are very similar to all the other species on the planet, with us being closest to chimpanzees, then to other apes, then to other primates, then to other mammals, then to other animals with a vertebrate, etc.  Also, scientists have found inactive genes in various species exactly where they would expect to find them.  For instance, you can find the genetic code for teeth in bird DNA (as they descended from dinosaurs) but you will not find the code for mammary glands in lizard DNA (since that came about in mammals, which evolved after the reptiles.)  And this leads me to the next point...

2.  Evolution is dogmatic, just like a religion.  Guess what would happen if they started finding the genetic code for mammary glands in reptiles or the code for beaks in humans?  The whole theory would go out the door.  Not only that, but if we found rabbits in the same layers as dinosaurs, then evolution would go out the door.  The thing is, evolution remains the preeminent theory in biology because as more evidence, including fossils and genetic mapping, comes in, we find exactly what we expect to find, from birds that are kinda like dinosaurs (or is that dinosaurs that are kinda like birds?) to fish that are kinda like amphibians, to primates that are kinda like humans, but kinda like other apes.  What this means is that evolution is falsifiable.  There is a set of criteria that could disprove it, and it's this very important detail that makes something like Intelligent Design not a scientific theory.  In the case of ID and religious dogma, there is absolutely nothing that can ever disprove them.

3.  We "came from monkeys".  No.  We share a common ancestor with the other apes.  Nobody's saying we came from monkeys.

4.  We're the most evolved.  We are not "more" evolved than other animals.  Animals like sharks and alligators haven't changed much for millions upon millions of years.  Why haven't they evolved to become smart enough where they could eventually build cities and develop writing?  Because they don't need to.  They survive, and they're great at doing what they're doing.  If all of a sudden their prey got a heck of a lot smarter, they'd either die off or start getting smarter themselves.  And if the latter ever happens, we might very well be screwed.

5.  Species A suddenly gives birth to Species B.  Some creationists out there seem to think that evolution means that one day you have a dog, and it might give birth to a cat.  Or they think that it will give birth to a half-dog/half-cat.  The thing is, another thing that would completely throw evolutionary theory out the window would be if a particular species suddenly gave birth to a totally different species.  Evolution doesn't occur among a individuals.  It's about populations, and the changes are gradual.  Do yourself a favor and google the term "ring species".  What you'll find, for instance, are different species of lizards spread out over a geographical area.  The ones that are closest to each other, geographically, will be technically different species, but they can still mate and produce fertile offspring.  This leads us to believe that the two species are related.  However, when you get two different species that are further apart, and even though they can reproduce with their nearest neighbors, they cannot reproduce with each other.  So, species X can reproduce with species Y, and species Y and reproduce with species Z, but species X cannot reproduce with species Z.  (It's a bit more drawn out and complicated than that, but hopefully you get the idea.)

6.  There is evidence for micro-evolution but not macro-evolution.  You know who never seems to use these terms?  Actual biologists.  The idea behind this fallacy is that while there is clear, undisputed evidence that one lizard species can evolve into another one, there is no way that reptiles eventually evolved into mammals.  It's like saying that an infant grows into a child, but there's no way that he could ever become an adult.  Again, see what I wrote about fossils and DNA - there is evidence that all forms of life are related.  If we can observe one lizard become a completely different species within the course of our lifetime, why is it so unfathomable that given enough time and distance, we could get two species that are even further apart?

7.  You can't be religious and believe in evolution.  There are plenty of Christians who accept evolution without any problem.  It's only a problem if you rely on Biblical literalism, but there are plenty of prominent biologists who are Christian, and there have been many prominent religious organizations that have made official statements accepting evolutionary theory, including the Catholics, Lutherans, and Anglicans, off the top of my head.

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