Deep Dive
Why is the discovery of opalised monotreme fossils at the Australian Museum considered groundbreaking?
The discovery is groundbreaking because it revealed a whole new age of mammals, the Age of Monotremes, which were previously unknown. It doubled the known number of ancient monotreme species from Lightning Ridge and suggested that egg-laying mammals ruled Australia during the age of dinosaurs.
Why did Tim Flannery and Chris Helgen find the opalised fossils in the Australian Museum?
They found the fossils during a period of lockdown in 2022 when they were confined to Sydney. They decided to explore the museum's vast collection of 22 million specimens, leading to the discovery of the opalised monotreme fossils.
What makes the monotremes discovered at Lightning Ridge so unique?
The monotremes discovered at Lightning Ridge are unique because they represent new genera and families, indicating a high diversity of egg-laying mammals. They also possess specialized features like electro-sense and venomous spurs, which are not found in other mammals.
Why were the opalised monotreme fossils overlooked for so long?
The fossils were overlooked due to the mundane reasons of changing scientific priorities and the fossils being off-site. Despite the best efforts of paleontologists like Elizabeth Smith, they were only returned to the museum recently.
What does the discovery of the tribus venid mammal in Victoria suggest about the origin of modern mammals?
The discovery suggests that modern mammals, including placentals and marsupials, may have originated in the Southern Hemisphere, particularly in Australia, rather than the Northern Hemisphere as previously believed.
Why is the idea of a Southern Hemisphere origin for modern mammals controversial?
The idea is controversial because it challenges the long-standing belief that modern mammals evolved in the Northern Hemisphere. Northern Hemisphere colleagues have been reluctant to accept this new hypothesis, leading to a resounding silence or icy reception.
What is the significance of the tribus venid teeth found in the Southern Hemisphere?
The tribus venid teeth are significant because they indicate a key step in the evolution of modern mammalian teeth, which allow for complex food processing. The presence of these teeth in the Southern Hemisphere suggests that the ancestors of modern mammals may have originated there.
How did the discovery of the tribus venid mammal in Victoria impact the scientific community?
The discovery initially met with skepticism and resistance from Northern Hemisphere colleagues. However, it has sparked a re-evaluation of the fossil record and the potential for a Southern Hemisphere origin of modern mammals.
What role did Tim Flannery play in the discovery of the tribus venid mammal?
Tim Flannery revisited the implications of Tom Rich's original 1997 paper on the tribus venid mammal and collaborated with Tom, Chris Helgen, and others to compile new evidence. This led to the publication of a paper suggesting a Southern Hemisphere origin for modern mammals.
What is the significance of the electro-sense in monotremes?
The electro-sense in monotremes is a sophisticated adaptation that allows them to detect electrical signals from other organisms, making it easier to find food in dark environments. This sense is unique and highly evolved, contributing to their survival in polar conditions.
- Discovery of opalised monotreme fossils in the Australian Museum during COVID-19 lockdowns.
- Three new species of ancient monotremes discovered.
- These fossils doubled the known number of ancient monotremes from Lightning Ridge.
- The discovery suggests an "Age of Monotremes" in Australia during the dinosaur age.
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