Victoria's Polar Cretaceous Tetrapods
47+ Years of Research: Following in the footsteps of Ferguson
Professor Pat Vickers-Rich and Dr Tom Rich
Monash University; Melbourne Museum
Monash University; Melbourne Museum
Thanks to the efforts of more than 700 volunteers over four and a half decades, Museums Victoria has acquired a modest collection of Early Cretaceous polar tetrapods. This record largely consists of isolated teeth and bones along with a few partial skeletons and numerous ichnites or footprints. Most diverse are the dinosaurs with about a dozen different ones recognised, two or three different turtles, six mammals, one or more pterosaurs and plesiosaurs, and two or three temnospondyl amphibians.
Turtles and ornithopod dinosaurs are known from partial skeletons. Many of the other taxa are known only from a few or even a single bone. Owing to this sparsity, many of the identifications are provisional. Despite that, however, quite unexpected insights are
suggested by the available specimens. Theropod dinosaurs present seem to be a mix between cosmopolitan forms and strictly Gondwana ones showing a particularly close relationship to those from South America. Ceratopsian dinosaurs thrived in the Northern Hemisphere but one, and possibly a second, ulna is the only available Southern Hemisphere record of this group, relatives of Triceratops.
Three of the mammals are therians but definitely not marsupials or metatherians. They have been suggested to quite unexpectedly be eutherians that evidently went extinct in Australia before the metatherians arrived or were stem therians that are neither metatherian nor eutherian. Another mammal is the oldest cimolodontan multituberculate, a group that thrived later in the Northern Hemisphere from the Late Cretaceous to the Eocene. Could they have arisen in the Southern Hemisphere and subsequently dispersed to the Northern Hemisphere? The oldest known monotreme occurs in Victoria along with a larger, younger taxon that is likely to be a monotreme, but possibly not.
Temnospondyl amphibians thrived from the Early Carboniferous, 330 million years ago, to the Late Jurassic, 145 million years ago. Two or three Victorian taxa are the very youngest known at 125 million years ago, tens of millions of years after all the other global forms had gone extinct.
Although the Bass Coast tetrapods are about 20 million years older than the Otway ones, the only outstanding difference between the two assemblages is that the temnospondyls are restricted to the older sites and the crocodilians, to the younger when there was no longer evidence for the presence of permafrost and the environment was more suitable for them.
In summary, about half the tetrapod taxa now known to be present in the Early Cretaceous of Victoria were not unexpected. But the others were complete surprises, and more surprises likely await with further work in the future. This ancient polar region in the Cretaceous of southern Australia certainly protected some forms (like the temnospondyls) by excluding others (like the crocodiles until late in the story) due to the climate, when Australia was connected to Antarctica.
Turtles and ornithopod dinosaurs are known from partial skeletons. Many of the other taxa are known only from a few or even a single bone. Owing to this sparsity, many of the identifications are provisional. Despite that, however, quite unexpected insights are
suggested by the available specimens. Theropod dinosaurs present seem to be a mix between cosmopolitan forms and strictly Gondwana ones showing a particularly close relationship to those from South America. Ceratopsian dinosaurs thrived in the Northern Hemisphere but one, and possibly a second, ulna is the only available Southern Hemisphere record of this group, relatives of Triceratops.
Three of the mammals are therians but definitely not marsupials or metatherians. They have been suggested to quite unexpectedly be eutherians that evidently went extinct in Australia before the metatherians arrived or were stem therians that are neither metatherian nor eutherian. Another mammal is the oldest cimolodontan multituberculate, a group that thrived later in the Northern Hemisphere from the Late Cretaceous to the Eocene. Could they have arisen in the Southern Hemisphere and subsequently dispersed to the Northern Hemisphere? The oldest known monotreme occurs in Victoria along with a larger, younger taxon that is likely to be a monotreme, but possibly not.
Temnospondyl amphibians thrived from the Early Carboniferous, 330 million years ago, to the Late Jurassic, 145 million years ago. Two or three Victorian taxa are the very youngest known at 125 million years ago, tens of millions of years after all the other global forms had gone extinct.
Although the Bass Coast tetrapods are about 20 million years older than the Otway ones, the only outstanding difference between the two assemblages is that the temnospondyls are restricted to the older sites and the crocodilians, to the younger when there was no longer evidence for the presence of permafrost and the environment was more suitable for them.
In summary, about half the tetrapod taxa now known to be present in the Early Cretaceous of Victoria were not unexpected. But the others were complete surprises, and more surprises likely await with further work in the future. This ancient polar region in the Cretaceous of southern Australia certainly protected some forms (like the temnospondyls) by excluding others (like the crocodiles until late in the story) due to the climate, when Australia was connected to Antarctica.
About the speakers
Emerita Professor Patricia Vickers-Rich and Dr Tom Rich have been the trailblazers over 50 years of their research in vertebrate palaeontology in Victoria. Their research has focussed on the environmental changes that have impacted Australia and Gondwana and how this shaped the evolution of Australia’s fauna and flora.
Dr Pat Vickers-Rich is an expert in the origin and evolution of Australasian vertebrates and their environments over the past 400 million years, and during the last two decades has added a major project on the Precambrian-Phanerozoic boundary, with an emphasis on Namibia, leading three UNESCO IGCP (493, 597, 673) projects related to this new research area. She had in the past a special interest in Australian avian fossils, and led research teams to investigate the origin and development of terrestrial vertebrates and birds around the world, and in addition over the past 20+ years led fieldwork and research on the late Precambrian in Africa, Southeast Asia, , Russia, South America, Iran and Saudi Arabia.
Dr Tom Rich is Senior Curator of Vertebrate Palaeontology at Museums Victoria. With the aid of just over 700 volunteers, his primary research has focused on finding and analysing the mammals, dinosaurs, pterosaurs, birds, turtles, plesiosaurs and the temnospondyl amphibian Koolasuchus that lived in what was polar Victoria between 105 and 130 million years ago. Only two specimens of these were known in Victoria when Tom joined the museum in 1974. His fieldwork and research has gone beyond Australia in places like South and North America, South Africa and Antarctica.
Together they have led a major effort since the 1970s to locate new fossil localities in Victoria as well as in Namibia. Together the couple described the dinosaur genera Leaellynasaura and Timimus, naming them after their daughter and son, Leaellyn and Tim Rich along with Tim Flannery, respectively. Their field work in Victoria informs their research on interpreting changing climate and biogeographic affinity of the biota of Gondwana during the past 120 million years. And beyond that, much of the material gained on these various expeditions have led to a number of global exhibitions in cooperation with global colleagues, which have raised funds to support this research and field work: Dinosaurs from China, The Great Russian Dinosaurs Expo, Wildlife of Gondwana, DinoQuest, etc.
Emerita Professor Patricia Vickers-Rich and Dr Tom Rich have been the trailblazers over 50 years of their research in vertebrate palaeontology in Victoria. Their research has focussed on the environmental changes that have impacted Australia and Gondwana and how this shaped the evolution of Australia’s fauna and flora.
Dr Pat Vickers-Rich is an expert in the origin and evolution of Australasian vertebrates and their environments over the past 400 million years, and during the last two decades has added a major project on the Precambrian-Phanerozoic boundary, with an emphasis on Namibia, leading three UNESCO IGCP (493, 597, 673) projects related to this new research area. She had in the past a special interest in Australian avian fossils, and led research teams to investigate the origin and development of terrestrial vertebrates and birds around the world, and in addition over the past 20+ years led fieldwork and research on the late Precambrian in Africa, Southeast Asia, , Russia, South America, Iran and Saudi Arabia.
Dr Tom Rich is Senior Curator of Vertebrate Palaeontology at Museums Victoria. With the aid of just over 700 volunteers, his primary research has focused on finding and analysing the mammals, dinosaurs, pterosaurs, birds, turtles, plesiosaurs and the temnospondyl amphibian Koolasuchus that lived in what was polar Victoria between 105 and 130 million years ago. Only two specimens of these were known in Victoria when Tom joined the museum in 1974. His fieldwork and research has gone beyond Australia in places like South and North America, South Africa and Antarctica.
Together they have led a major effort since the 1970s to locate new fossil localities in Victoria as well as in Namibia. Together the couple described the dinosaur genera Leaellynasaura and Timimus, naming them after their daughter and son, Leaellyn and Tim Rich along with Tim Flannery, respectively. Their field work in Victoria informs their research on interpreting changing climate and biogeographic affinity of the biota of Gondwana during the past 120 million years. And beyond that, much of the material gained on these various expeditions have led to a number of global exhibitions in cooperation with global colleagues, which have raised funds to support this research and field work: Dinosaurs from China, The Great Russian Dinosaurs Expo, Wildlife of Gondwana, DinoQuest, etc.
Professor Patricia Vickers-Rich
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Dr Tom Rich
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