02 Oct World’s Oldest-Known Tadpole
You may have seen the news recently whereby researchers studying in Patagonia, Argentina, discovered what is considered the largest and oldest-known tadpole. This Jurassic amphibian lived around 161 million years ago and was found on the bottom of a pond where it had been hidden for millions of years.
The tadpole is a juvenile of the extinct species Notobatruchus degiustoi and the adult frog would have looked very similar to today’s frogs.
The newly found tadpole measures 16cm from tip to tail, and the research team suggesting it likely died just before its frog metamorphosis.
The fossil of a tadpole found in Argentina is so well preserved that eyes and nerves are visible. (Credit: Chuliver et al., Nature, 2024)
The specimen was extremely well preserved, with some soft tissue imprinted into the fossil in dark marks on the rock. The researchers analysed these soft tissues and were able to confirm that many features of tadpoles today — like being filter feeders — existed even during the Jurassic period.
Before this discovery it was assumed that frogs millions of years ago also started life as tadpoles, but this is the first proof from such an ancient frog species.
“One of the most groundbreaking aspects of this finding is that it provides the first evidence for the presence of a tadpole, followed by a drastic metamorphosis … from the very beginning of the evolutionary history,” Dr Chuliver Pereyra, palaeontologist from Maimonides University and the lead author of the paper, said.
Read more: https://www.abc.net.au/news/science/2024-10-31/tadpole-giant-fossil-argentina/104531222