Nov. 23 (UPI) -- The ancient teeth of conodonts, one of Earth's earliest vertebrates, have offered paleontologists new proof of parallel evolution.
Despite living in distinct geographical regions, different groups of conodonts, eel-like creatures, adapted to new habitats in nearly identical ways.
Researchers detailed their discovery this month in the journal Proceedings of the Royal Society B.
Conodonts swam the planet's seas from 500 to 200 million years ago. Their cone-shaped teeth can be found trapped in sedimentary rocks all across the globe. Scientists estimate there were around 3,000 conodont species.
"Scientists have suspected for several years now that a certain subspecies known as Sweetognathus conodonts developed several parallel evolutionary adaptations," study co-author Emilia Jarochowska said in a news release.
For the study, Jarochowska and her colleagues in Germany partnered with a group of scientists in Canada who have collected Sweetognathus teeth from all over the world, including Bolivia and Russia.
"As we now have such a good knowledge of tectonics over the history of the Earth, we can rule out the possibility that organisms from these regions were ever in contact with each other," said Jarochowska, a paleontologist at Friedrich Alexander University in Germany.
Using high-resolution imagine technology, researchers produced 3D models and mathematical descriptions of several dozen conodont teeth.
The morphologies present in the teeth confirmed what scientists suspected -- conodonts repeatedly adapted in similar and predictable ways to different food sources in a variety of geographic locations.
The new analysis also confirmed that the teeth recovered from Bolivia and Russia belonged to two species with a common ancestor.
"We were able to prove that two lineages of Sweetognathus in two different parts of the world followed the same developmental pattern," Jarochowska said. "That is further proof for the theory of evolution -- and for the effectiveness of international collaboration."