Darwin Day.

Way back in July 2011, when I started this blog, my first post was about a common misconception regarding the theory of evolution by natural selection.

Since today is Darwin Day, I thought I would revisit the topic. (Happy 205th Birthday Charles!)

Evolution is consistently in the media, and is often presented as something that still requires debating, as "just a theory", or as some skewed version of itself. One of the biggest problems is that evolution by natural selection is viewed as being mutually exclusive with religion. Last I checked, Pope John Paul II was a man of pretty strong faith, and he declared evolution to be a fact, so clearly the two can be reconciled. (Phil Platt, the Bad Astronomer, wrote an excellent column about it here)

From here.

Another problem is the issue of language. Words that have one definition in science can have very different meanings in other areas (such as work, law, hypothesis, or that dreaded one, theory). 

One of the words that causes problems is "fitness", as in survival of the fittest.  What does it mean to be fit? Does one have to go to the gym and bench a lot of weight to become fit?

Survival of the fittest at its most basic should really be regarded as survival of those best suited to their environment. Features and behaviors that benefit a organism in one environment might be a detriment in another. 

But fitness also is determined by how successful you are, not only at surviving, but at having your offspring survive to reproductive age, which ensures the passing on of your genes. (My grade 10's are often appalled when I tell them that, from a biology standpoint, if you don't reproduce you are a 'failure'). 

There is also an indirect type of fitness which provides explanation for colony and/or pack behavior. While individuals themselves may not reproduce, they benefit from helping close relatives rear offspring, as the offspring of close relatives contain similar genes, and the survival of those genes is still ensured. 

This difference between definitions of fitness can explain all sorts of physiological adaptations and behavioral adaptations, but often times the link to fitness is not obvious, lending the impression that the trait is not advantageous and therefore would not be selected for if evolution works the way it is stated. The difference between these definitions also highlights the  need for clear communication. Darwin himself knew he was making arguments that went against the popularly held beliefs of man's supremacy over animals, and that acceptance of his ideas was easily challenged in the eyes of the general public due ignorance about the nuances of language. 

I personally think that Chuck would be rolling in his grave if he knew that the debates that raged in the early years of his theory were still being held today, over 150 years after the publication of Origin. 

My Darwin v Lamarck tee has shrunk too much to wear...

...but I did wear these awesome earrings in honor of Darwin Day!