Wednesday, October 7, 2009

Is There Devolution?

Can evolution run backward?  Scientists say no.
...But, until recently, scientists had never really tested the biological law — first proposed in 1905 — that evolution couldn’t run in reverse. No one expects whole organisms to mutate back into their evolutionary antecedents. But what about the proteins we’re made up of? Under the right circumstances, can they find their way back in time?
The answer, it turns out, is no.
A University of Oregon research team has tried, in essence, to return a protein — called a glucocorticoid receptor — to one of its ancestral states by reversing the mutations that produced the modern version of the receptor. They discovered that the mutations happened in two stages — two separate groups of mutations. The trouble, they report in the current issue of Nature, was that each separate cluster of mutations produced a dead receptor, no matter which one was chosen first. In other words, there was no way the protein could select a preferable state that would lead it, in nature, toward its ancestral form.
Evolution opens gateways into the future. But it appears to close them — firmly — behind it as well.
Inserted from <NY Times>
But sometimes scientists are just plain wrong.  Devolution does exist, and here’s the proof!


ivan said...

A corollary?

News item:

Move over, Lucy. And kiss the missing link goodbye.

Scientists today announced the discovery of the oldest fossil skeleton of a human ancestor. The find reveals that our forebears underwent a previously unknown stage of evolution more than a million years before Lucy, the iconic early human ancestor specimen that walked the Earth 3.2 million years ago.

I'm surprised the creationists weren't sharp enough to use this new finding as ammunition.

TomCat said...

Ivan, GW will always be the missing link to me.

ivan said...

I can sort of imagine a chart of devolution here. But back on all fours?

TomCat said...

All fours, Ivan? Snakes don't have four legs. They slither. :-)

Stimpson said...

Are we not men? We are Devo!

AdB said...

Straight answer to a straight question:

Yes -- Bush is a product of devolution.

TomCat said...

Cute, Stimson.

Welcome Anna. I remember you from HB's blog. Amen to that.