Evolution, creationism, and intelligent design are words that many people have extremely strong opinions about. Regardless of how you feel about why the laws of nature are what they are, which have evidently allowed us to exist, the evidence for the validity of the theory of evolution with one major mechanism being natural selection is absolutely overwhelming. That said, this is often very hard to communicate to people, especially those with strong biases against what they perceive as the implications of evolution, how evolution works, and why the case for it is so compelling.

Thankfully, there is a person calling him/herself cdk007 making youtube videos like this one to explain how evolution works, and why arguments against it are invalid, with dauntingly demonstrative examples:

The explanation basically boils down to, regardless of how life started, once you have even the simplest life in place that reproduces, mutates, and is subject to natural selection, you will get evolution. While reproduction and mutation are random (with far more variation occurring in sexual reproduction over asexual reproduction), natural selection is not random. The fact that certain traits are selected causes events that would be exceedingly improbable at random to occur all the time.

This video is excellent, and there are many others (the Bad Astronomer likes this one); I recommend them to anyone who is looking for simple, compelling examples of how this complicated biological process works. In fact, the only explanations that I’ve ever found easier to understand were watching Episode II of Carl Sagan’s Cosmos series and watching the off-Broadway play Trumpery, a fascinating play about the scientific and personal struggles of Charles Darwin (and I think Michael Cristofer deserves to be showered with accolades for his performance as Darwin).

Comments

  1. #1 Robert Piercy
    February 26, 2008

    Natural selection does not account for an increase in information within a genome. Nor does it account for mutations between “kinds.”

    It does, however, account for Hitler’s rationale in speeding up the process by ridding the world of “lesser evolved” humans.

  2. #2 Robert Piercy
    February 26, 2008

    “The number of intermediate varieties which have formerly existed on earth must be truly enormous. Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and gravest objection which can be urged against my theory.”

    - Charles Darwin

  3. #3 ethan
    February 26, 2008

    Robert,

    Thanks for your comments! On your first count, natural selection, by itself, does not account for an increase in information within a genome. But natural selection with either random mutations or sexual reproduction (or both) does account for an increase in information.

    On your second count, you are now becoming part of the argument between “gradualism” and “punctuated equilibrium” advocates. Does change occur painstakingly slowly over many many generations, or only in rapid bursts when selection pressures are extreme? The jury is still out on that one, but punctuated equilibrium would account for “the most obvious and gravest objection” to Darwin’s theory.

    Thanks for the comment; you remind me that I haven’t put up a post about biology in a long time. Check out http://startswithabang.com/?p=140