Custom Search

Friday, November 27, 2009

New species: Or maybe not?

At Wired Science, we are informed "Birth of New Species Witnessed by Scientists" (November 16, 2009):
On one of the Galapagos islands whose finches shaped the theories of a young Charles Darwin, biologists have witnessed that elusive moment when a single species splits in two.

In many ways, the split followed predictable patterns, requiring a hybrid newcomer who’d already taken baby steps down a new evolutionary path. But playing an unexpected part was chance, and the newcomer singing his own special song.
My best guess is that if the girls stop dropping by, he will soon be either singing a different tune or a bachelor. Note the qualifications:
The future of the species is far from certain. It’s possible that they’ll be out-competed by other finches on the island. Their initial gene pool may contain flaws that will be magnified with time. A chance disaster could wipe them out. The birds might even return to the fold of their parent species, and merge with them through interbreeding.

But whatever happens, their legacy will remain: New species can emerge very quickly — and sometimes all it takes is a song.
Hmmm. If a song is really "all it takes," it probably isn't a new species.

Siamese yowl differently from other cats, and their behaviour often diverges, but they are not a different species.

Why be so desperate to find an example of speciation?

Typically, species prefer their own when they can meet n' greet easily. Sometimes that won't happen. Successful species are often flexible about intermediates - which likely hinders speciation.

In this news story, reporter Brandon Keim deserves considerable credit for admitting the difficulties. Maybe some fragments of news about the problems are getting through.


Links to this post:

Create a Link

<< Home

Who links to me?