Paddlefish's Doubled Genome May Question Theories On Limb Evolution
By -- - SCIENCE DAILY
Added: Wed, 08 Aug 2012 14:50:33 UTC
Thanks to rod-the-farmer for the link
The American paddlefish -- known for its bizarre, protruding snout and eggs harvested for caviar -- duplicated its entire genome about 42 million years ago, according to a new study published in the journal Genome Biology and Evolution. This finding may add a new twist to the way scientists study how fins evolved into limbs since the paddlefish is often used as a proxy for a more representative ancestor shared by humans and fishes.
"We found that paddlefish have had their own genome duplication," said Karen Crow, assistant professor of biology at San Francisco State University. "This creates extra genetic material that adds complexity to comparative studies. It may change the way we interpret studies on limb development."
In order to study how human limbs develop, scientists compare the limb-building genes found in mice with fin-building genes found in fishes. Previous research on paddlefish has suggested that fishes possessed the genetic toolkit required to grow limbs long before the evolution of the four-limbed creatures (tetrapods) that developed into reptiles, birds, amphibians and mammals.
In the last decade, paddlefish have become a useful benchmark in evolutionary studies because their position on the evolutionary tree makes them a reasonably good proxy for the ancestor of the bony fishes that evolved into tetrapods such as humans. However, the fact that paddlefish underwent a genome duplication could complicate what its genes tell us about the fin-to-limb transition, says Crow.
Stephen Cave - Financial Times Comments
What we really know about our evolutionary past – and what we don’t
- - Ancestors Trail Walk Comments
WALK DARWIN’S TREE OF LIFE ~ 26 AUGUST 2012 - event begins on Saturday 25 August
Liat Clark - Wired.co.uk Comments
Astrophysicists simulate 14 billion years of cosmic evolution in high resolution
Alok Jha - The Guardian Comments
Cambridge scientists claim DNA overlap between Neanderthals and modern humans is a remnant of a common ancestor
- - Science Blog Comments
Why, after millions of years of evolution, do organisms build structures that seemingly serve no purpose?
Charles Choi - CBS News Comments
Four decades ago, in 1972, the Koobi Fora Research Project discovered the enigmatic fossilized skull known as KNM-ER 1470 which ignited a now long-standing debate about how many different species of early Homos existed.
MORE BY --
-- - UC Davis News Comments
How quickly can new species arise? In as little as 6,000 years, according to a study of Australian sea stars.
-- - The Telegraph Comments
Hotel boss Wayne Bartholomew in unrepentant about his new choice of bedside reading for his guests despite an outcry from church authorities.
-- - CNN Comments
Sally Ride, the first American woman to fly in space, died Monday after a 17-month battle with pancreatic cancer, her company said. She was 61.
-- - Science Daily 7 Comments
New research supports the idea that human speech evolved less from vocalizations than from communicative facial gestures.
-- - BBC News 11 Comments
Researchers have identified what they say are the oldest-known musical instruments in the world.
-- - Rationalist Society of Australia 73 Comments
A debate between Chris Stedman, PZ Myers, and Leslie Cannold from April 15, 2012.