Fossilised 'Giant' discovered on Kangaroo Island
Fossils of a giant new species from the long-extinct group of sea creatures called trilobites have been found on Kangaroo Island, South Australia.
The finding is adding important insights to our knowledge of the Cambrian 鈥榚xplosion鈥, the greatest diversification event in the history of life on Earth, when almost all animal groups suddenly appeared over half-a-billion years ago.
Trilobites, which had hard, calcified, armour-like skeletons over their bodies, are related to modern crustaceans and insects. They are one of the most successful fossil animal groups, surviving for about 270 million years (521 to 252 million years ago). Because of their abundance in the fossil record, they are considered a model group for understanding this evolutionary period.
鈥淲e decided to name this new species of trilobite听Redlichia rex听(similar to听Tyrannosaurus rex) because of its giant size, as well as its formidable legs with spines used for crushing and shredding food 鈥 which may have been other trilobites,鈥 says听James Holmes, PhD student with the 成人大片鈥檚 School of Biological Sciences, who led the research.
The preservation of trilobite 鈥榮oft parts鈥 such as the antennae and legs is extremely rare. The new species was discovered at the Emu Bay Shale on Kangaroo Island, a world-renowned deposit famous for this type of preservation. The findings have been published in the听by a team of scientists from the 成人大片, South Australian Museum and the University of New England.
The new species is about 500 million years old, and is the largest Cambrian trilobite discovered in Australia. It grew to around 30 cm in length, which is almost twice the size of other Australian trilobites of similar age.
鈥淚nterestingly, trilobite specimens from the Emu Bay Shale 鈥 including听Redlichia rex听鈥 exhibit injuries that were caused by shell-crushing predators,鈥 says senior study author听, from the 成人大片 and the South Australian Museum.
鈥淭here are also large specimens of fossilised poo (or coprolites) containing trilobite fragments in this fossil deposit. The large size of injured听Redlichia rex听specimens and the associated coprolites suggests that either much bigger predators were targeting听Redlichia rex, such as听Anomalocaris听鈥 an even larger shrimp-like creature 鈥 or that the new species had cannibalistic tendencies.鈥
One of the major drivers of the Cambrian explosion was likely an evolutionary 鈥渁rms race鈥 between predators and prey, with each developing more effective measures of defence (such as the evolution of shells) and attack.
鈥淭he overall size and crushing legs of听Redlichia rex听are a likely consequence of the arms race that occurred at this time鈥 says James Holmes. 鈥淭his giant trilobite was likely the terror of smaller creatures on the Cambrian seafloor.鈥
Specimens of听Redlichia rex听and other Emu Bay Shale fossils are currently on display in the South Australian Museum.
Article from the News Archives.
The finding is adding important insights to our knowledge of the Cambrian 鈥榚xplosion鈥, the greatest diversification event in the history of life on Earth, when almost all animal groups suddenly appeared over half-a-billion years ago.
Trilobites, which had hard, calcified, armour-like skeletons over their bodies, are related to modern crustaceans and insects. They are one of the most successful fossil animal groups, surviving for about 270 million years (521 to 252 million years ago). Because of their abundance in the fossil record, they are considered a model group for understanding this evolutionary period.
鈥淲e decided to name this new species of trilobite听Redlichia rex听(similar to听Tyrannosaurus rex) because of its giant size, as well as its formidable legs with spines used for crushing and shredding food 鈥 which may have been other trilobites,鈥 says听James Holmes, PhD student with the 成人大片鈥檚 School of Biological Sciences, who led the research.
The preservation of trilobite 鈥榮oft parts鈥 such as the antennae and legs is extremely rare. The new species was discovered at the Emu Bay Shale on Kangaroo Island, a world-renowned deposit famous for this type of preservation. The findings have been published in the听by a team of scientists from the 成人大片, South Australian Museum and the University of New England.
The new species is about 500 million years old, and is the largest Cambrian trilobite discovered in Australia. It grew to around 30 cm in length, which is almost twice the size of other Australian trilobites of similar age.
鈥淚nterestingly, trilobite specimens from the Emu Bay Shale 鈥 including听Redlichia rex听鈥 exhibit injuries that were caused by shell-crushing predators,鈥 says senior study author听, from the 成人大片 and the South Australian Museum.
鈥淭here are also large specimens of fossilised poo (or coprolites) containing trilobite fragments in this fossil deposit. The large size of injured听Redlichia rex听specimens and the associated coprolites suggests that either much bigger predators were targeting听Redlichia rex, such as听Anomalocaris听鈥 an even larger shrimp-like creature 鈥 or that the new species had cannibalistic tendencies.鈥
One of the major drivers of the Cambrian explosion was likely an evolutionary 鈥渁rms race鈥 between predators and prey, with each developing more effective measures of defence (such as the evolution of shells) and attack.
鈥淭he overall size and crushing legs of听Redlichia rex听are a likely consequence of the arms race that occurred at this time鈥 says James Holmes. 鈥淭his giant trilobite was likely the terror of smaller creatures on the Cambrian seafloor.鈥
Specimens of听Redlichia rex听and other Emu Bay Shale fossils are currently on display in the South Australian Museum.
Article from the News Archives.
Newsletter & social media
Join us for a sensational mix of news, events and research at the Environment Institute. Find out about听new initiatives and听share with your friends what's happening.
听听听