News: Study questions 'cost of complexity' in evolution
- From: "Robert Karl Stonjek" <rstonjek@xxxxxxxxxxxxxx>
- Date: Tue, 1 Apr 2008 16:07:36 -0500 (EST)
Study questions 'cost of complexity' in evolution
Higher organisms do not have a "cost of complexity" - or slowdown in the
evolution of complex traits - according to a report by researchers at Yale
and Washington University in Nature.
Biologists have long puzzled over the relationship between evolution of
complex traits and the randomness of mutations in genes. Some have proposed
that a "cost of complexity" makes it more difficult to evolve a complicated
trait by random mutations, because effects of beneficial mutations are
diluted.
"While a mutation in a single gene can have effects on multiple traits, even
as diverse as the structures of brain, kneecap and genitalia, we wondered
how often random mutation would affect many traits" said lead author Gunter
Wagner professor and chair of ecology and evolutionary biology at Yale. The
phenomenon wherein mutation in a single gene can have effects on multiple
traits is known as pleiotropy.
This study showed that most mutations only do affect few traits. Further,
the effect of an individual mutation is not dampened because of its effects
on other traits.
Observing 70 skeletal characteristics in the mouse, the researchers
identified total of 102 genomic regions that affect the skeleton. They
concluded that substitution in each genome segment affected a relatively
small subset of characteristics and that the effect on each characteristic
increased with the total number of traits affected.
"You wouldn't expect to make a lot of random adjustments - at the same
time - to tune up a car," said Wagner. "Similarly, it appears that tuning up
a complex trait in a living organism is well coordinated and the effects of
pleiotropy are more focused than we thought."
Citation: Nature 452: (March 27, 2008) doi:10.1038/nature06756
Source: Yale University
http://www.physorg.com/news126203217.html
Posted by
Robert Karl Stonjek
.
- Prev by Date: A question about human genetic diversity in Africa
- Next by Date: Re: A question about human genetic diversity in Africa
- Previous by thread: A question about human genetic diversity in Africa
- Next by thread: Re: News: Study questions 'cost of complexity' in evolution
- Index(es):
Relevant Pages
|
