Wednesday, December 23, 2009

First Report of Venom in Bird Lineage

This image of fossilized Sinornithosaurus shows the raptor's long, grooved fangs. It lived in prehistoric forests of northeastern China that were filled with a diverse assemblage of animals including other primitive birds and dinosaurs. (Credit: David A. Burnham, PhD, University of Kansas, Biodiversity Institute)

Poisonous Prehistoric 'Raptor' Discovered in China

ScienceDaily (Dec. 22, 2009) — A group of University of Kansas researchers working with Chinese colleagues have discovered a venomous, birdlike raptor that thrived some 128 million years ago in China. This is the first report of venom in the lineage that leads to modern birds.

"This thing is a venomous bird for all intents and purposes," said Larry Martin, KU professor and curator of vertebrate paleontology at the Natural History Museum and Biodiversity Institute. "It was a real shock to us and we made a special trip to China to work on this."

The KU-China team's findings will be published in the early edition of the Proceedings of the National Academy of Sciences during the week of Dec. 21. "We think it's going to make a big splash," said Martin.
The article's authors are Enpu Gong, geology department at Northeastern University in Shenyang, China, and researchers Martin, David Burnham and Amanda Falk at the KU Natural History Museum and Biodiversity Institute.

The dromaeosaur or raptor, Sinornithosaurus (Chinese-bird-lizard), is a close relative to Velociraptor. It lived in prehistoric forests of northeastern China that were filled with a diverse assemblage of animals including other primitive birds and dinosaurs.

"This is an animal about the size of a turkey," said Martin. "It's a specialized predator of small dinosaurs and birds. It was almost certainly feathered. It's a very close relative of the four-winged glider called Microraptor."
The venom most likely sent the victim into rapid shock, shrinking the odds of retaliation, escape or piracy from other predators while the raptor manipulated its prey.

"You wouldn't have seen it coming," said Burnham. "It would have swooped down behind you from a low-hanging tree branch and attacked from the back. It wanted to get its jaws around you. Once the teeth were embedded in your skin the venom could seep into the wound. The prey would rapidly go into shock, but it would still be living, and it might have seen itself being slowly devoured by this raptor."

The genus had special depressions on the side of its face thought by the investigators to have housed a poison gland, connected by a long lateral depression above the tooth row that delivered venom to a series of long, grooved teeth on the upper jaw. This arrangement is similar to the venom-delivery system in modern rear-fanged snakes and lizards. The researchers believe it to be specialized for predation on birds.
"When we were looking at Sinornithosaurus, we realized that its teeth were unusual, and then we began to look at the whole structure of the teeth and jaw, and at that point, we realized it was similar to modern-day snakes," Martin said.

Sinornithosaurus is represented by at least two species. These specimens have features consistent with a primitive venom-delivery system. The KU-China research team said it was a low-pressure system similar to the modern Beaded lizard, Heloderma, however the prehistoric Sinornithosaurus had longer teeth to break through layers of feathers on its bird victims.

The discovery of features thought to be associated with a venom-delivery system in Sinornithosaurus stemmed from a study of the anatomy and ecology of Microraptor by the joint Chinese-KU team. They now are seeking to discover if Microraptor may have possessed a similar poison-delivery system.

Story Source:
Adapted from materials provided by University of Kansas, via EurekAlert!, a service of AAAS.

University of Kansas. "Poisonous Prehistoric 'Raptor' Discovered in China." ScienceDaily 22 December 2009. 23 December 2009 <­ /releases/2009/12/091221212630.htm>.

Monday, December 14, 2009

Scientists make penguin DNA discovery

Scientists make penguin DNA discovery at ZSL 

Monday, 14, Dec 2009 12:01

By Sarah Garrod.

Scientists have developed a new penguin DNA profiling technique which is being used for the first time to study how they migrate between colonies.

Researchers from the Zoological Society of London (ZSL) and the University of Sheffield have identified genetic markers that can be used to track the movement of penguins.

They say ultimately the discovery could determine whether Antarctica's changing climate is driving penguins from their favoured breeding sites.

ZSL's own penguinologist, Tom Hart said: "Knowing how penguins are responding to climate change is vital to conservation efforts.

"If we understand how their populations are changing, we can do something about it, such as making sure that our protected areas are in the right place for penguins in 100 years time."

The researchers say penguins are not only threatened by climate change, but are also under increasing pressure from direct competition with fisheries.

Studying them is notoriously difficult because they live in very harsh environments and are hard to track, therefore this new monitoring tool enables scientists to follow their populations and address the threats that they face.