Researchers Find Tadpole Fossil Dating Back 161 Million Years!
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A team of scientists looking for dinosaur fossils in 2020 made a rare discovery. They found a well-preserved tadpole dating back 161 million years to the middle Jurassic period. This discovery breaks the record for the oldest known tadpole fossil by about 20 million years!
The ancient amphibian was found in Argentina's Santa Cruz Province. Encased inside a limestone slab, it was astonishingly intact. It even had eyeballs, gills, and nerves. Such preservation is rare, as tadpoles' bodies are mostly cartilage and soft tissue. These usually do not fossilize well.
“It’s not only the oldest tadpole ever discovered, but also the most exquisitely preserved,” said Mariana Chuliver, the study's lead researcher.

The tadpole belonged to a now-extinct frog species and measured about 6 inches (15 cm). This is about the same size as the adult of its species. Chuliver attributes the tadpole's large size to the abundance of food and space available during the Jurassic period. This allowed even tadpoles to grow larger than usual.
The researchers revealed their findings in the journal Nature on October 30, 2024. They note that the discovery fills an important gap in understanding frog evolution. Some scientists previously believed the earliest frogs may not have gone through a tadpole stage. But this fossil proves they did — at least as far back as 161 million years ago.
Chuliver hopes to secure more funding to return to the site and search for additional fossils, uncovering new secrets.
Resources: Smithsonianmag.com, Livescience.com

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39 Comments
- damonhalpin5 monthsAWSOME! I love dinosaurs especially when we find new species! SCIENCE IS SO COOL!!!
- thiago115 monthsIt’s not Jurassic World it’s foggy world. Also it’s incredibly cool how preserved it was!
- suri02205 monthsHow long did that frog live?
- honizitesijo5 monthsAMAZING!!! I can't believe it is so preserved after all this time!!!
- duckies5 monthsWoah! I never knew this! But this is so cool I never knew any of this before now!
- 1_emma_15 monthsWow this is super cool!🤩
- suri02205 monthsI didn’t know that fossils can be found between rocks!😮😮
- milkfanforever5 monthsSame here!
- gayatri5 monthsNice
- mariohx6 monthsgreat
- 852128sophie6 monthsI can't believe this