Thursday, February 12, 2009

The problem with Darwin's theory

Biologists agree Darwin's theory of evolution explains how a species advances, but the theory does not explain how one species branches off from another (NY Times). In other words, Darwin's paradigm shifting work, "On the Origin of Species," didn't actually explain how a species originates.

The question is a fascinating one. Why does one species suddenly pull away from another? Work in genetics labs is shedding light on the issue. Geneticists are close to defining a "speciation gene." According to the NY Times, "The newly discovered genes cause reproductive isolation between two groups by causing their offspring, or hybrids, to be infertile or die."

But why would one group of organisms split off and develop these species-protecting genes? Sexual selection may be the first step. In Physalaemus petersi, a small Amazonian frog, certain females are attracted to males with one type of call (a "whine") and certain other females are attracted to males with a different call (a "whine and squawk). Continued, exclusive breeding between these exclusive groups may eventually lead to the development of speciation genes that split them apart forever.

(photo via

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I started pound360 to channel my obsession with vitamins, running and the five senses. Eventually, I got bored focusing on all that stuff, so I came back from a one month hiatus in May of 2007 (one year after launching Pound360) and broadened my mumblings here to include all science.