Established in 2020 Wednesday, April 17, 2024


Scientists estimate the weight of two giant extinct amphibians
Artist’s reconstruction of Eryops megacephalus (left) and Paracyclotosaurus davidi (right). Image courtesy: Josè Vitor Silva.



SYDNEY.- A team of Australian scientists led by UNSW Sydney paleontologist Lachlan Hart has calculated the body mass of two ancient amphibians.

The last of the temnospondyls—amphibians that look more like crocodiles—became extinct during the Cretaceous period, about 120 million years ago, after thriving on Earth for more than 200 million years.

Now a team of scientists led by Lachlan Hart, a paleontologist and Ph.D. candidate in the School of Biological, Earth & Environmental Sciences at UNSW Sydney, has assessed various methods of estimating the weight of these unique extinct animals. The team's study is published in Palaeontology.

"Estimating mass in extinct animals presents a challenge, because we can't just weigh them like we could with a living thing," said Mr. Hart. "We only have the fossils to tell us what an animal looked like, so we often need to look at living animals to get an idea about soft tissues, such as fat and skin."

Temnospondyls as case studies
Mr. Hart said temnospondyls were "very strange animals."

"Some grew to enormous sizes, six or seven meters long. They went through a larval (tadpole) stage just like living amphibians. Some had very broad and round heads—such as Australia's Koolasuchus, recently named as the Victorian State Fossil Emblem—and others, like the temnospondyls we used in this study, had heads that were more croc-like."

The 1.8 meter-long Eryops megacephalus lived during the Permian period in what is now the U.S., while the slightly longer Paracyclotosaurus davidi is known from the Triassic of Australia. The more aquatically inclined Paracyclotosaurus was the heftier of the two, tipping the scales at roughly 260 kilograms, where Eryops was a more modest 160 kilograms.

"The size of an animal is important for many aspects of their life," said Mr. Hart. "It impacts what they feed on, how they move and even how they handle cold temperatures. So naturally, paleontologists are interested in calculating the body mass of extinct creatures so we can learn more about how they lived.

"There have been several studies on body mass estimation in other groups of extinct animals, such as dinosaurs, but not extensively on temnospondyls.

"They survived two of Earth's Big Five mass extinction events which makes them a very interesting case study on how animals adapted following these global catastrophes," Mr. Hart said.

Because temnospondyls have no direct living relatives, the team of scientists had to assemble a selection of five modern "analogs" (such as the Chinese Giant Salamander and the Saltwater Crocodile) to test a total of 19 different body mass estimation techniques to determine their suitability for use in temnospondyls.

"We found several methods which gave us consistently accurate body mass estimations in our five living animals, which included using mathematical equations and 3-dimensional digital models of the animals," said Dr. Nicolas Campione from the University of New England, Armidale, an authority on body mass estimation who was also involved in the study. "We hypothesized that as these methods are accurate for animals which lived and looked like temnospondyls, they would also be appropriate for use with temnospondyls."

Dr. Matthew McCurry, senior lecturer in earth science at UNSW, and co-author on the study said, "This work has shown there are multiple methods for estimating mass in temnospondyls.

"We don't need the whole skeleton to do this, as some methods involve using the width of the skull or the circumference of the legs. The work will be useful for paleontologists because many fossils we find are only of one or two parts of the skeleton."







Today's News

November 25, 2022

1,700-year-old spider monkey remains point to earliest evidence of primate captivity, translocation and gift diplomacy

A radical new approach in synthetic chemistry

Researchers develop a new type of light-sensitive nanoparticle to help identify ectopic pregnancy

Gene that guides earliest social behaviors could be key to understanding autism

Cell therapy process for heart regeneration may advance treatment of cardiovascular disease

A possible game changer for next generation microelectronics

Scientists convert waste paper into battery parts for smartphones and electric vehicles

Fluxonium qubits bring the creation of a quantum computer closer

Decades of air pollution undermine the immune system, lymph nodes study finds

A regime shift in an Arctic marine ecosystem that's likely to become permanent

Study finds you should keep your cats inside for the sake of their health and the surrounding environment

Scientists estimate the weight of two giant extinct amphibians

Quick-closing valve allows fish to rapidly regulate the water in their cells

A simpler path to better computer vision

Corals found to be beneficial in saving other corals

Researchers recreate the adrenal gland in a petri dish

Arctic carbon conveyor belt discovered

Microlaser chip adds new dimensions to quantum communication



 


Editor & Publisher: Jose Villarreal
Art Director: Juan José Sepúlveda Ramírez



Tell a Friend
Dear User, please complete the form below in order to recommend the ResearchNews newsletter to someone you know.
Please complete all fields marked *.
Sending Mail
Sending Successful