Recent discoveries show that these birds had enormous heads and very impressive beaks. Bird skulls are particularly fragile, and until very recently, no one had much of an idea how the head of a thunderbird looked. The most common finds have been vertebrae, the long bones of the hind limbs, and toe bones. Since then, many thunderbird bones have been found throughout Australia. The first bone of a thunderbird was encountered in the late 1820s in the Wellington Caves, New South Wales, by a team led by Thomas Mitchell, but almost 50 more years went by until the first species of thunderbird was formally identified by Richard Owen.
Essentially, they were ducks that grew to enormous proportions in the isolated refuge of Australia. The origins of the thunderbirds are very different from the origins of the ratites. Outward similarities in nature can be misleading, and the parallelism between the thunderbirds and the ratites is simply due to the phenomenon of convergent evolution. The Australian thunderbirds share certain characteristics with the ratites, such as an absent keel bone (the anchor for the attachment of large flight muscles) tiny wings, useless for flying long legs and powerful feet. Seven species of Australian thunderbird have been identified from remains found throughout the continent, and they range in size from animals the size of the cassowary to Stirtons thunderbird (Dromornis stirtoni), a 3-m-tall, 400-kg whopper that may challenge the elephant bird, Aepyornis maxiumus, for the mantle of the largest bird ever. Collectively, these feathered brutes are known as the dromornithids, or thunderbirds, and they appear to have been diverse, common animals of prehistoric Australia. Up until 30,000 years ago, Australia supported even more types of giant flightless bird, which were very distinct from the ratites. These two species are closely related to the other ratites, the giant flightless birds that evolved on the immense southern landmass of Gondwanaland: the ostrich of Africa, the rhea of South America, the kiwis of New Zealand, and the extinct moa and elephant birds of New Zealand and Madagascar, respectively.Īustralian Thunderbird- Stirtons thunderbird ( Dromornis stirtoni) was probably the largest Australian thunderbird and one of the heaviest birds ever to have lived.
Today, Australia is home to two species of giant flightless bird: the emu of the bush and plains and the cassowary of the northern forests. Where did it live? The bones of these birds are known only from Australia. When did it become extinct? The last of the Australian thunderbirds died out around 30,000 years ago. Scientific classification: Phylum: Chordata Class: Aves Order: Anseriformes Family: Dromornithidae
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