Scientists estimate the weight of two giant extinct amphibians

The body mass of two ancient toads has been calculated by a group of Australian scientists.

After living on Earth for more than 200 million years, the last of the temnospondyls, which looked like crocodiles, died out around 120 million years ago.

Various methods of estimating the weight of extinct animals have been assessed by a team of scientists. The study was published in a journal.

Mr. Hart said that estimating mass in extinct animals was a challenge. We don't have fossils to tell us what an animal looked like, so we need to look at living animals to get an idea about soft tissues.

The case studies include tmnospondyls.

Mr. Hart said that temnospondyls were very odd.

Some grew to six or seven meters in length. They went through a stage similar to a salamander. The temnospondyls we used in this study had heads that were more croc-like.

The Eryops megacephalus lived in what is now the U.S., while the Paracyclotosaurus davidi lived in Australia. The heftier of the two was the Paracyclotosaurus, which tipped the scales at 260 kilogram, compared to 160 kilogram for Eryops.

Mr. Hart said that the size of an animal is important for a lot of things. It affects how they move and how they handle cold temperatures. Paleontologists want to know how extinct creatures lived so they calculate their body mass.

Several studies on body mass estimation have been done on dinosaurs, but not on temnospondyls.

Two of Earth's Big Five mass extinction events made them an interesting case study on how animals adapt to global catastrophes.

The team of scientists had to test a total of 19 different body mass estimation techniques to see if they were suitable for use in the future.

"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 Nicolas Campione, an authority on body mass estimation. As these methods are accurate for animals which lived and looked like temnospondyls, they are appropriate for use with them.

There are multiple methods for estimating mass in temnospondyls according to Dr. Matthew McCurry, senior lecturer in earth science at the University of New South Wales.

We don't need the whole skeleton to do this as there are other ways to do it. Many fossils we find are only a small part of the skeleton.

A case study on the estimation of body mass in temnospondyls was published in the journal Palaeontology. There is a book titled "pala.12629."

Journal information: Palaeontology