Australasian Science: Australia's authority on science since 1938

Survival of the Littlest

© Peter Schouten from Feathered Dinosaurs: The Origin of Birds

Jinfengopteryx, a feathered bird-like dinosaur. © Peter Schouten from Feathered Dinosaurs: The Origin of Birds

By Michael Lee

Birds co-existed with their dinosaur ancestors for nearly 100 million years, but eventually outlived them. Two new studies have revealed why.

The full text of this article can be purchased from Informit.

The transformation of lumbering ground-dwelling dinosaurs into agile flying birds may have seemed fanciful in the 19th century, but it now represents a poster child for evolution. The dinosaurian ancestry of birds had been suspected ever since Archaeopteryx was unearthed from a slate quarry in Germany more than 150 years ago. This famous transitional fossil had wings and feathers like a bird, but retained a long reptilian tail, toothy jaws, and legs with sickle-shaped claws like those of carnivorous dinosaurs.

Spectacular discoveries of bird-like dinosaurs in the past few years have cemented the ancestory of birds within dinosaurs. More and more avian traits have been found in bipedal theropod dinosaurs, such as wishbones, long flexible arms, large brains and light hollow bones. We now also know that relatives of Tyrannosaurus rex and Velociraptor were adorned with feathers. Many of the most revealing fossils are from northern China, where a Pompeii-style eruption more than 120 million years ago covered these dinosaurs in fine volcanic ash, preserving their feathers with such detail that even their colours can be reconstructed.

We are now very certain that birds are a subgroup of dinosaurs, just like humans are a subgroup of mammals. However, some important aspects of the dinosaur–bird transition remain elusive.

Birds first appeared more than 150...

The full text of this article can be purchased from Informit.