Australian scientists have studied the largest bird brain in history for the first time, New Atlas reported. Paleontologists examined the brain shells of the extinct Dromornithidae family of non-flying birds, including some of the largest birds ever, and conducted some strange evolutionary experiments on them.
Dromornithidae is a group of giant non-flying birds that lived in Australia from the New Age about 25 million years ago until they ben extinct about 50,000 years ago. They are also known as mihirungs and mean “giant birds” in indigenous languages. In addition, the bird is also known as the Thunderbird. The largest species can grow up to 3 meters high and weigh about 600 kg.
The scientists focused on four mihirungs skull fossils that lived within this time range. Dromornis Murrayi lived about 24 million years ago; Dromornis Planei and Droornis Ilbandornis, both lived about 12 million years ago; and Dromornis Stirtoni, from about 7 million years ago.
They performed CT scans of the brain shells of these ancient birds, then created 3D models of them and compared them to similar (albeit smaller) modern cousins. Doing so reveals the size and shape of the brain, which is most similar to that of modern chickens. Scientists are thus able to reproduce their biology and way of life.
“Combined with their large, forward-looking eyes and very large gills, the shape of their brains and nerves suggests that these birds are likely to have developed stereoscopic vision or depth perception and feed on tender leaves and fruit,” said lead author Dr. Warren Handley.
The latest species, Droornis Stirtoni, is of particular interest. As the second-largest known bird, its head is shaped strangely, which the team says causes the shape of the brain to be just as weird.
Trevor Worthy said: The bird has the largest skull, but behind the huge gills is a strange skull. To accommodate the muscle movement of this huge mole, the skull has become taller and wider than it is, so the brain inside is squeezed flat. It appears that the evolution of these giant birds was caused by the natural environment conditions in Australia. ”
The study was published in the journal Diversity.