Latest news with #Kotevski
Yahoo
25-02-2025
- Science
- Yahoo
Aussie fossils reveal historic discovery
A landmark discovery has revealed the previously-unknown existence of a large apex predator on the prehistoric Australian continent and uncovered a predator hierarchy unique to the region. The research describes five theropod fossils discovered between 1988 and 2023 in Bunurong/Boonwurrung Country (Bass Coast) and the Eastern Marr Country (Otway Coast). Theropods are classified as carnivorous dinosaurs that are able to walk on two legs with hollow, thin-walled bones and usually small forelimbs – the tyrannosaurus is a famous example. The formal identification of the fossils was led by Monash University PhD candidate Jake Kotevski and the Museums Victoria Research Institute It shows that Victoria's ancient ecosystem was dominated by large powerful megaraptorids (6–7 metres long) alongside smaller carcharodontosaurs (2–4 metres long) and agile, metre-long unenlagiines, or 'southern raptors'. The discovery marks the first evidence of carcharodontosaurs in Australia's dinosaur record and is significant for contribution to the global theropod fossil record. 'The discovery of carcharodontosaurs in Australia is groundbreaking,' Mr Kotevski said. 'It's fascinating to see how Victoria's predator hierarchy diverged from South America, where carcharodontosaurs reached Tyrannosaurus rex-like sizes up to 13 metres, towering over megaraptorids. Here, the roles were reversed, highlighting the uniqueness of Australia's Cretaceous ecosystem.' Two of the newly-described fossils represent the oldest known megaraptorids globally. 'Museum collections are crucial to advancing our understanding of prehistoric life', vertebrate palaeontology collection manager at Museums Victoria Research Institute Tim Ziegler said. 'Specimens preserved in the State Collection for decades – unidentifiable until now – are providing new insights into the evolution of dinosaur ecosystems'. The findings highlight Victoria's unique Cretaceous fauna and offer 'compelling evidence of faunal interchange' between Australia and South America through Antarctica during the Early Cretaceous,' senior curator at Museums Victoria Research Institute Dr Thomas Rich said. Key fossil sites are still being surveyed by Mr Kotevski and the team as part of Monash's Dinosaur Dreaming project. It has uncovered more than 10,000 fossil bones and teeth since the project began in 1994 – including at least seven different dinosaurs, three groups of mammals, birds, pterosaurs, plesiosaurs, turtles and fishes.
Yahoo
20-02-2025
- Science
- Yahoo
Double jackpot: Australia finds oldest megaraptor along with new dinosaur fossils
Paleontologists have uncovered fossils of not one but two apex predator groups coexisting in ancient Victoria, Australia. First, they have identified the oldest megaraptorid fossils ever found, pushing back the known timeline for this group of theropods. Second, experts have uncovered the first definitive evidence of another theropod group, "carcharodontosaurs," in Australia. These discoveries, unearthed along Victoria's stunning coastline, paint a vivid picture of a Cretaceous ecosystem unlike any other. The fossil study was led by Museums Victoria Research Institute and Monash University. Five theropod dinosaur fossils were discovered in two locations in Victoria: the upper Strzelecki Group (121.4-118 million years old) and the Eumeralla Formation (113-108 million years old). Theropods were a diverse group of bipedal, mostly carnivorous dinosaurs like Tyrannosaurus rex. The discovered fossils reveal that Victoria's ancient ecosystem was a complex predator landscape. Megaraptorids, reaching 6-7 meters in length, were the apex predators. These were a group of medium to large-sized theropod dinosaurs that lived during the Cretaceous period. These dinosaurs possessed sickle-shaped claws on their second toe, which were likely used for slashing and tearing prey. Alongside the dominant megaraptorids, the ancient Victorian ecosystem also included smaller carcharodontosaurs, which ranged from 2 to 4 meters in length. In South America, carcharodontosaurs were the giants, unlike in Australia. 'The discovery of carcharodontosaurs in Australia is groundbreaking,' said Jake Kotevski, PhD student. 'It's fascinating to see how Victoria's predator hierarchy diverged from South America, where carcharodontosaurs reached Tyrannosaurus rex-like sizes up to 13 metres, towering over megaraptorids. Here, the roles were reversed, highlighting the uniqueness of Australia's Cretaceous ecosystem,' Kotevski added. The ecosystem was also home to agile, meter-long unenlagiines, sometimes called "southern raptors." These smaller, more lightly built dinosaurs were likely swift hunters, possibly specializing in smaller prey. The discovery of two of these fossils as the oldest known megaraptorids worldwide is a significant find. It pushes back the timeline of when these predators roamed the Earth and gives insights into their evolution. Furthermore, the presence of these ancient megaraptorids in Australia, along with other theropod species, suggests that Australia's dinosaur fauna played a vital role in the larger Gondwanan ecosystem. 'The findings not only expand Australia's theropod fossil record but offer compelling evidence of faunal interchange between Australia and South America through Antarctica during the Early Cretaceous. The findings also challenge previous assumptions about body-size hierarchies in Gondwanan predator ecosystems highlighting Victoria's unique Cretaceous fauna,' explained Thomas Rich, senior curator of vertebrate paleontology at Museums Victoria Research Institute. The study demonstrates that museum collections are essential for scientific breakthroughs. Some of these fossils, hidden away for decades, are now filling the gaps in the dinosaur puzzle. Under the Dinosaur Dreaming project, the research team will continue to explore fossil sites where the large megaraptorid was found. As per the press release, this project has already yielded over 10,000 fossils, representing diverse prehistoric life, including dinosaurs, mammals, birds, pterosaurs, plesiosaurs, turtles, and fish. The findings were published in the Journal of Vertebrate Paleontology.
The Independent
20-02-2025
- Science
- The Independent
Giant ‘megaraptor' dinosaur species discovered in Australia
Giant 20-foot-long raptor dinosaurs once roamed Australia, according to a new study that could rewrite the evolutionary history and hierarchy of predators on the continent. The research, published in the Journal of Vertebrate Paleontology on Thursday, identifies five new species of four-legged dinosaurs whose fossils were unearthed from Victoria's coastline. Researchers excavated dinosaur shin bones and vertebrae at two fossil sites in Victoria – the upper Strzelecki Group dated to 121 million years ago and the Eumeralla Formation from about 113 million years ago. The fossils provide unique insights into an ancient Australian ecosystem dominated by powerful 'megaraptor' dinosaurs measuring 6-7 metres in length. Two of the new megaraptor species are the oldest known globally and shed light on the evolutionary history of the group that includes the iconic velociraptor made famous by Jurassic Park films. The latest study highlights the role played by Australia 's dinosaurs in the ecosystems of the ancient world, a large part of which was clustered into the giant supercontinent Gondwanaland. These 'megaraptorids' lived alongside the smaller 'carcharodontosaurs', which were 2-4 metres long, as well as the even smaller but more agile 'unenlagiines' or 'southern raptors'. 'Two megaraptorid specimens from the upper Strzelecki Group demonstrate that this clade had achieved large body size at the time of its first appearance in the fossil record,' scientists said. Jake Kotevski, a co-author of the study, called the latest discovery 'groundbreaking' due to the unique insights it offers into Australia's ecosystem during the Cretaceous era between 145 and 65 million years ago. 'It's fascinating to see how Victoria's predator hierarchy diverged from South America, where carcharodontosaurs reached Tyrannosaurus rex -like sizes up to 13 metres, towering over megaraptorids,' Mr Kotevski said. 'Here, the roles were reversed, highlighting the uniqueness of Australia's Cretaceous ecosystem.' The new study offers 'compelling evidence' for the interchange of animals between Australia and South America via Antarctica during the Early Cretaceous era, scientists said. It also highlights the key contributions of community volunteers working alongside seasoned researchers to further understanding of Australia's dinosaurs. 'The findings also challenge previous assumptions about body-size hierarchies in Gondwanan predator ecosystems highlighting Victoria's unique Cretaceous fauna,' said Thomas Rich, senior curator of vertebrate palaeontology at Museums Victoria Research Institute.
