Frozen accidents

There's a term used in evolutionary biology - "frozen accidents".  Generally it means that the state of something in biology is the way it is just because it's the way it is - that there is no overall purpose or benefit for something being done a certain way.  It's an accident of evolution, and it's just stuck, or frozen, because we're so far down the line that changing it would be near impossible - that natural selection, or any of the evolutionary forces are not sufficient to make it any better.  

The first example of this I was introduced to was the genetic code.  The genetic code is a series of 3 letter "words" or strings of individual bases of DNA that are translated into a particular amino acid (the building blocks of proteins).  Throughout life on earth, the genetic code is the same for the vast majority of organisms (mitochondria and a few organisms have different codes, but they're very close to the "universal" genetic code).  The genetic code is redundant - multiple words translate to the same amino acid.  However, there didn't seem to be any explanation for why certain DNA words stood for particular amino acids.  This was a frozen accident - the vast majority of life on earth has the same genetic code because we have a common ancestor that had this code, and since it's such a vital part of how things work, it's hard to change it.  If you change the code in any one organism, you would end up changing the makeup of all the proteins in the cell, and they most likely wouldn't function properly anymore.  So we're stuck with a genetic code from a couple of billion years ago.  Fortunately, research hypothesizes that this code is actually fairly optimal - it minimizes the impact of the most common mutations.  Amino acids have basic chemical properties - some like water, some stay away from water (like fats), some are basic, some are acidic, etc.  The genetic code is such that a common mutation in the DNA is more likely to change the amino acid that's coded for to another amino acid that acts kinda like the original amino acid.  But researchers found that if this is the reason for the genetic code being the way it is, it isn't the best it could be.  

And that's kinda the point of this blog - to discuss topics in biology in sync with their evolutionary origins and how those origins aren't really founded in "intelligent design" because if there was a designer and that designer was intelligent, that designer would have done a better job.

As far as I'm concerned, I hold a Ph.D. in Biology, specializing in Molecular Evolutionary Biology.  I'm a practicing Roman Catholic and I manage to believe in God and still think that evolution exists.  My purpose is education - because if people are going to spread the word that evolution doesn't exist, I'm going to fight back by teaching people how evolution does exist and why it's really the best explanation anyone has for the beauty and diversity of the life that surrounds us.