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View Full Version : Old speciation theory given new life


ToddStark
September 11th, 2006, 03:45 PM
Theodosius Dobzhansky's 70 year old theory that speciation could sometimes be kicked off by relocating genes (rather than by the more common gradual accumulation of mutations) has resurfaced thanks to recent genetics research by J.P. Masly at the University of Rochester.

Dobzhansky had studied fruit flies in the infant days of genetic research in 1930. He mapped out how it might be possible for sections of chromosomes to relocate themselves in a genome. Those mobile sections can cause sterility in inter-species hybrids, which can act as a speciation pressure. Masly found a way to test the theory, also involving fruit flies.

In theory, the idea was sound, but scientists long debated whether it actually happened in nature. Eventually a competing theory involving the gradual accumulation of mutations was shown to occur in nature so often that geneticists largely dismissed the moving gene hypothesis.

The finding, reported in today's issue of Science, reveals that scientists must reassess the processes involved in the origin of species. The beginnings of speciation, suggests the paper, can be triggered by genes that change their locations in a genome.

Source: Science Daily summary of the Science article (http://www.sciencedaily.com/releases/2006/09/060908194141.htm)

James Brody
September 12th, 2006, 03:06 PM
No great surprise!

Every so often I trip across speculation that we sometimes catch genes and modifications from viruses...

And Svante recently? announced that some of you and me was borrowed from gorillas!

JB