Meet Tyrannosaurus Pecks

Published on Thursday 24 April 2008 22:25

The humble farmyard chicken may be descended from T-rex

ONE was feared as a giant carnivore that stalked the earth in search of prey.

The other is a farm animal and a byword for senseless behaviour.

But the mighty Tyrannosaurus rex has more in common with the humble chicken than you might think.

A scientific study of ancient protein dating back 68 million years suggests that chickens could in fact be direct descendants of the King of the Dinosaurs.

Scientists from the United States analysed the structure of tiny shreds of protein extracted from a fossilised T-rex bone.

The discovery of protein in dinosaur bones was itself a surprise, as organic material was not thought to survive this long.

While scientists have long suspected that birds, and not reptiles, are dinosaurs' closest living relatives, for years that theory rested on similarities in bird and dinosaur skeletons.

But now, it seems, close ties between the fearsome predator and the humble chicken can be confirmed.

Researchers from Harvard University, in Massachusetts, analysed molecules from a shred of Tyrannosaurus rex protein, along with that of 21 modern species, to study their evolutionary links.

Their findings indicated that the giant beasts, which reigned the earth for more than 100 million years, share common ancestry with chickens and ostriches.

Scientists found that, at a molecular level, T-rex was much more like our feathered friends than alligators and lizards.

Similarities with frog and newt protein were also found.

Dr John Asara, from the Beth Israel Deaconess Medical Centre in Boston, which also took part in the research, said: "We determined that T-rex, in fact, groups with birds – ostrich and chicken – better than any other organism that we studied. We also show that it groups better with birds than modern reptiles, such as alligators and green anole lizards."

An evolutionary biologist, Dr Chris Organ, from Harvard University, said: "Even though we only had six peptides – just 89 amino acids – from T-rex, we were able to establish these relationships with a relatively high degree of support.

"With more data, we'd likely see the T-rex branch on the phylogenetic tree (which shows the evolutionary links between different species) between alligators and chickens and ostriches, though we can't resolve this position with currently available data."

The scraps of T-rex protein were disentangled from a thigh bone discovered in 2003 on a barren fossil-rich stretch of land spanning the states of Wyoming and Montana.

Two years later, scientists discovered that soft tissue known as collagen could be salvaged from the fossilised bone – allowing them to establish the unlikely link.

Collagen is the same substance injected into the lips, and other areas of the body, in cosmetic surgery procedures.

Dr Organ's team say their technique could help to reveal evolutionary relationships between other living and extinct organisms. A similar analysis of protein from a mastodon bone found close similarities between the extinct pachyderm and modern elephants.

FOWL FACTS

&#149 An adult hen weighs between 1kg and 3kg.

&#149 The world hen egg-laying record is 371 in 364 days.

&#149 A hen lives an average of six years, but can live up to 20 years.

&#149 Chickens were domesticated about 8,000 years ago.

&#149 There are more than 150 varieties of domestic chicken.

&#149 A chicken takes 21 days to hatch.

&#149 The chicken was once considered a sacred animal, symbolising the sun.

&#149 Americans consume eight billion chickens a year.

&#149 A chicken's heart beats 280-315 times a minute.

&#149 It takes 4lb of feed to make one dozen eggs.

&#149 The word "chicken" also means a person who lacks confidence, is irresolute and wishy-washy.

&#149 Alektorophobia is the term for fear of chickens.

DINOSAUR DATA

&#149 An adult T-rex weighed five to seven tonnes.

&#149 They measured about 40ft long and 20ft high.

&#149 A healthy T-rex was thought to live about 40 years.

&#149 Tyrannosaurus Rex became extinct 65 million years ago.

&#149 T-rex had 9in serrated teeth that were continually replaced.

&#149 Tyrannosaurus Rex means "tyrant lizard king".

&#149 T-rex ate large dinosaurs, such as Triceratops.

&#149 The first T-rex skeleton was found by Barnum Brown in 1902.

&#149 Fossils have been found in the US, Canada and Mongolia.

&#149 About 30 incomplete T-rex fossils have been found.

&#149 An asteroid probably killed T-rex and other dinosaurs. Other theories include disease and climate change.