Saturday, March 18, 2006

The King Kong of Penguins

NZ fossil penguin shows modern bird groups lived with Dinosaurs
New Waimanu genus of ancient penguins described by Otago Scientists
05 April 2006

A newly-recognised species of ancient penguin, studied and named by University of Otago palaeontologists, is helping to refute the theory that many modern bird groups did not emerge until after the dinosaurs were wiped out.

The Otago scientists' official description of the Waimanu penguin genus, which lived in the shallow seas off eastern New Zealand between 60 and 62 million years ago, is published in an upcoming issue of the international journal Molecular Biology and Evolution.

Reconstruction of Waimanu

The fossil penguins, found at the Waipara River in Canterbury in the 1980s, are the oldest reported in the world, says Associate Professor Ewan Fordyce of the University's Geology Department.

"These 'proto' penguins were about the size of yellow-eyed penguins and probably looked a bit like shags. It's very unlikely that they could fly, but their wing bones were compressed and dense, which would allow their wings to be used to swim underwater," says Assoc Prof Fordyce.

Their official description of the genus appears as part of a research article suggesting that many modern bird groups evolved well before the dinosaurs died out. The research is a collaborative synthesis of fossil study and DNA detective work, he says.

"With the geological age of the penguins fossils firmly dated, Massey's Allan Wilson Centre for Molecular Ecology and Evolution could predict how far back in time other groups of living birds originated," he says.

To predict the time of origin of living birds, Wilson Centre researchers led by Professor David Penny examined the genetic evidence from distant penguin relatives such as storks, albatrosses, ducks and moas. Genetic studies were carried out both in New Zealand and Sweden, by Wilson Centre graduate student Kerryn Slack.

By using the age of the fossil penguins as a reference point, and then examining the birds' pattern of evolutionary interrelationships through studying their DNA, the researchers were able to establish a new time frame for when groups of modern birds branched out.

"It became clear that as these early penguins lived in southern seas not long after the extinction of dinosaurs, then other more distantly related bird groups must have been established even earlier – which goes directly against a recent theory from the United States," says Assoc Prof Fordyce.

A prominent US scientist, Professor Alan Feduccia, has claimed that many living bird groups are geologically young, having emerged after the catastrophic extinction event 65 million years ago. Prof Feduccia argues that most birds from before this event represented ancient groups which disappeared along with dinosaurs and are not related to living forms.

"In contrast, our study suggests that many groups of living birds date well back in Cretaceous times, when the dinosaurs were thriving," says Assoc Prof Fordyce.

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