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What Darwin really meant by "natural selection" With all the controversy that still hovers over Charles Darwin’s theory of natural selection, it was a pleasure to hear FAU Associate Professor Colin R. Hughes clear up some misconceptions February 5 at a talk he gave at the Hagen Ranch Library in Delray, FL. The talk was being held to celebrate Darwin’s birthday (actually February 12). To me, particularly interesting was Prof. Hughes explanation of the phrase “survival of the fittest.” Hughes, a professor of genetics at Florida Atlantic University, explained that natural selection was much more complicated than that phrase would suggest; it is not some sort of “magic,” immediate formula that happens all the time in all situations. In fact, in order for it to come about, there have to be four variables in a species. Here’s an example he gave me later on using birds and their beaks. #1—VARIATION There must be variation among the individuals in a particular "characteristic.” For instance, some of the birds may have larger beaks, some smaller. #2—HERITABLE These variations must be “heritable.” That is, they are passed on to offspring. Bigger beaked birds have bigger beaked offspring. #3—OFFSPRING Individuals must vary in the number of offspring they have. Some birds produce more chicks than others. #4—ONE CHARACTERISTIC The number of offspring depends on variation in that characteristic. For example bigger beaked birds have more chicks than smaller beaked birds. If all these four statements are true, that particular version of the characteristic will be more common in the next generation. Using this example, the next generation of birds will have larger beaks on average. That is natural selection in beak size.
The Darwin Day event was sponsored by the Deerfield/Boca branch of Atheists and Secular Humanists of Florida (FLASH) a 401-c-3 organization, dedicated to the separation of government and religion.
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