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Wednesday, September 30, 2009

Feathery Four-winged Dinosaur Fossil Found In China Bridges Transition To Birds



Feathery Four-winged Dinosaur Fossil Found In China Bridges Transition To Birds

ScienceDaily (Sep. 29, 2009) — A fossil of a bird-like dinosaur with four wings has been discovered in northeastern China. The specimen bridges a critical gap in the transition from dinosaurs to birds, and reveals new insights into the origin evolution of feathers.

The transition from dinosaurs to birds is poorly understood because of the lack of well-preserved fossils, and many scientists argue that bird-like dinosaurs appear too late in the fossil record to be the true ancestors of birds.

In the journal Nature this week, Xing Xu and colleagues describe an exceptionally well-preserved fossil of Anchiornis huxleyi from the province of Liaoning, China. Long feathers cover the arms and tail, but also the feet, suggesting that a four-winged stage may have existed in the transition to birds.

Anchiornis huxleyi was previously thought to be a primitive bird, but closer inspection reveals that it should be assigned to the Troodontidae — a group of dinosaurs closely related to birds.

The authors date the fossil to the earliest Late Jurassic, meaning that it is the oldest bird-like dinosaur reported so far, and older than Archaeopteryx, the earliest known bird.

They conclude that the presence of such a species at this time in the fossil record effectively disputes the argument that bird-like dinosaurs appeared too late to be the ancestors of birds.

Journal reference:

1. Dongyu Hu, Lianhai Hou, Lijun Zhang, Xing Xu. A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus. Nature, 2009; DOI: 10.1038/nature08322

Adapted from materials provided by Nature.

Nature. "Feathery Four-winged Dinosaur Fossil Found In China Bridges Transition To Birds." ScienceDaily 29 September 2009. 30 September 2009 <http://www.sciencedaily.com­ /releases/2009/09/090928205415.htm>.

Monday, September 28, 2009

King penguins make a comeback



Posted Mon Sep 28, 2009 5:34am AEST

King Penguins re-populating in Southern Ocean

King Penguins were virtually wiped out on Macquarie Island about 100 years ago.

Scientists are celebrating the re-colonisation of king penguins on Macquarie Island in the Southern Ocean.

When Macquarie Island was discovered in 1810, it was teeming with king penguins, but by the turn of the century, hundreds of thousands of birds had been slaughtered for blubber oil.

Only a small colony of the birds survived at Lusitania Bay on the island.

Almost 100 years later, John van den Hoff from the Australian Antarctic Division says he is surprised to find King Penguins at the Macquarie Island isthmus where a century ago they had been exterminated.

"Without having read the historical accounts, we had no idea there were ever birds on the isthmus," he said.

He believes the population at Lusitania Bay has grown to the point that penguins are looking for more real estate.

"There are now 250 chicks in that colony and growing," he said.

"We hope it will continue to grow and perhaps the numbers will reach such a point on the isthmus that they'll have to move on to colonise other parts of the island as well."

Penguin biologist Barbara Wienecke says finding the population has recovered is a rare occurrence.

"There are only very few documented examples where colonies have popped up again," she said.

"All species have an extraordinary affinity to the colonies from which they would have left as fledglings, so to hear that a brand new colony is popping up on an island ... is really fantastic news."

Source:
http://www.abc.net.au/news/stories/2009/09/28/2697885.htm

Tuesday, September 15, 2009

Dee Boersma wins Heinz Award


September 15, 2009
Dee Boersma wins Heinz Award

Dee Boersma is among 10 recipients of the Heinz Family Foundation awards given to people whose achievements have fostered a cleaner, greener and more sustainable world.

Each recipient will receive $100,000 and a medallion inscribed with the image of the late Sen. John Heinz, R-Pa., whose environmental legacy is commemorated by the awards.

Boersma, a UW biology professor, and holder of the Wadsworth Endowed Chair in Conservation Science is being honored for her extensive field study of penguins and other sea birds to promote conservation and understanding human impact on marine environments. In an effort to better communicate issues of the natural world to the public, she launched Conservation Magazine a publication for cutting -edge science and smarter conservation (www.conservationmagazine.org). For more than 25 years she and her students, working with the Wildlife Conservation Society, have studied Magellanic penguins at the Punta Tombo reserve in Argentina. She has dubbed the penguins "marine sentinels" for their warning signs about the ocean environment. Her recent work has shown that, because of climate change and other factors, during the critical period of egg incubation the penguins at Punta Tombo must swim an average of 25 miles further in search of food than they did just 10 years ago.

The awards, announced Sept. 15, were established in 1993 to honor Heinz's legacy on environmental issues.

Learn more at the Heinz Awards website:
http://www.heinzawards.net/recipients/

Source:
http://mesh.biology.washington.edu/penguinProject/home/