I'm nearing my own birthday in a few days (the dreaded dirty thirty), but today, February 12th, is the 200th birthday of Charles Darwin, whose theory of evolution through natural selection is easily one of the greatest discoveries in the history of human knowledge.

In celebration of Darwin Day 2009, my fellow Americans should watch the Nova special about the debate surrounding evolution in America called Judgment Day: Intelligent Design on Trial on the PBS website. I especially recommend Chapter 6, which explains the difference between the common everyday use of the term "theory" (which implies unsupported "speculation") versus a scientific theory (which, according to the National Academy of Sciences, is "a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment"). Chapter 6 also presents one of the most compelling facts to support human evolution: the existence of vestigial centromeres and telomeres in Chromosome 2.

Sadly, 150 years after the first publication of Darwin's seminal book On the Origin of Species, many Americans still refuse to accept evolution as fact despite the (literally) mountains of evidence to support Darwin's theory. I spent last Thanksgiving arguing with a family friend who defiantly dismissed evolution as "just a theory" despite my futile attempts to educate her. She, like so many Americans, defies rationality and reason by subscribing to the so-called "Intelligent Design" theory, which is hardly a theory at all because it cannot be confirmed through observation and experiment nor can it make any predictions about the natural world. Evolution, however, has been confirmed over and over with each new piece of genetic and fossil evidence (e.g. Tiktaalik) and it can make accurate predictions about the natural world (i.e. Chromosome 2).

Happy Birthday Charles Darwin!!!