The extinction of the Australian thunderbirds 40,000 years ago was reportedly due to paralytic bone disease. Remote studies of some vertebrate paleontologists found that the birds' reproduction cycle changed gradually.
Further studies reveal that the demise of these dromornithids has another factor - their frail adaptability to the changing environment.
The enormous bone fragments of the thunderbirds were recently excavated in the remote town of Alice Springs and the mountain range of North Flinders.
South Africa's University of Cape Town Professor Anusuya Chinsamy-Turan said that the birds fought the rising hindrances of climate change, particularly in Australia, which became drier and hotter.
She added that the rapid climate challenges contributed to the breeding biology and reproduction cycle compared to the present-day emu birds.
The Thunderbird's Early Existence
The first largest species of Australian thunderbirds, scientifically referred to as Dromornis stirtoni, lived more than seven million years ago. They weighed more than 1300 pounds (lbs) and could grow up to 9-10 feet. The dromornithids could take up to 15 years to mature sexually and grow.
Professor Anuya added that the indicative span of time until these birds reach adult form and sexual maturity were factors in interpreting the evolutionary success and failure of possible survival up until the present time.
Genyornis newtoni is considered the last and tiniest flightless dromornis that lived in the later Pleistocene age when the climate season was far drier with significant seasonal variation and unforeseen droughts.
They were also referred to as the Demon-Ducks of Doom due to their humongous bills and how they stand. However, the Genyornis newtoni needed an extra few years to become fully dromornithidae, and they could grow six times as large as present-day emus.
Once they reach their full form, they can start breeding after their second year of life period and can grow up to 500-600 pounds (lbs).
Australia's Thunderbird that lived seven million years ago.
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Demon-Ducks Existence Challenge
The co-author of the research, Flinders University Professor Trevor Worthy, stated that the demon ducks lived alongside the emus before their demise. He added that "they (emus and thunderbirds) survived together through major climatic apprehension."
However, Professor Worthy mentioned that the Genyoris were better adapted, so they survived compared to their ancestors two million years ago.
But during the rise of drought surroundings, the norm changed, and the growing and breeding challenges occurred for the mihirungs compared to the emus.
Worthy also conveyed that the emu had a breeding strategy advantage with their human encounter 50,000 years ago, while the mihirung were perishing off within 10,000 years.
"In the end, the mihirungs lost the evolutionary race and an entire order of birds was lost from Australia and the world," he declared.
The study also revealed that the researchers found some unique burn prints in the eggshell fragments of the thunderbirds throughout Australia, a sign that humans intruded on the giant birds' nest for food.
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