Birds HISTORY

Birds

Birds are animals that have feathers and that are born out of hard-shelled eggs.

Some people think that what makes an animal a bird is its wings. Bats have wings. Flies have wings. Bats and flies are not birds. So what makes an animal a bird?

Introduction

In the recent upsurge of interest in the early evolution of birds, Australia has not contributed to the debates on bird-dinosaur relationships or on the origin of feathers or flight. Nonetheless, it does have interesting, albeit patchy, record of birds across the past 110 million years. The record is poor compared those of Europe and North America, in both temporal and faunistic representation. There are a few intervals with rich, diverse avian records, several scattered periods with small to moderate representations and some extensive gaps at critical times.

The earliest Australian record of birds, from the Early Cretaceous (110-100 million years ago -mya), comprises five small indeterminate feather impressions from Koonwarra, Victoria and a few small bones from southern Victoria, north central New South Wales and western Queensland. The feathers have been known for some time, but unfortunately the birds from which they came have not appeared from the deposits. Likewise, little can be said about the Victoria and New South Wales fossils.

The bones from Queensland can be attributed to an enantiornithine bird. The recognition of the subclass Enantiornithes has been a major advance in understanding bird evolution. These strange birds differed from modern birds in a variety of major features of the skeleton. They appear to have been the dominant lineage of birds through the Cretaceous, and their fossils are now known from every continent, including Australia. Like the dinosaurs, this group of morphologically diverse birds became extinct by the end of the Cretaceous. The Queensland fossils, which have been named Nanantius eos, show that these birds were in Australia.