Researchers from Portsmouth University have uncovered fossils from the oldest-known ancestors of most living mammals in southern England, a new study in Acta Palaeontologica Polonica reports.
The 145-million-year-old teeth belonged to extinct shrew-like animals that existed during the time of the dinosaurs. The team in the study analyzed the remains and came to the conclusion that they are the earliest remains ever found from mammals in the line the eventually led to humans.
”Here we have discovered from the Jurassic coast a couple of shrew-like things that are to date unequivocally our earliest ancestors,” said lead author Steve Sweetman, a researcher at Portsmouth University, according to BBC News.
The ancient mammals were small, furry creatures that likely first existed under the cover of night. Scientists believe they burrowed through the ground and dined on both insects and plants. Their teeth could pierce, cut, and crush food — which made them quite advanced for their time — and they were also worn. That suggests the shrews lived during a time where they thrived.
Researchers first uncovered the fossils while sifting through rock samples collected at Durlston Bay near Swanage. They have named the species Durlstotherium newmani.
This study is important because it could help shed light on a long-debated topic and help researchers build a better evolutionary timeline. Recent discoveries have dated the earliest mammals to 160 million years ago, but molecular data has directly refuted such claims. The new findings could put that debate to rest.
The ancient animals are the second oldest placental mammals ever found, suggesting that there is still a lot to learn about evolution during the Jurassic and Cretaceous period.
“The Jurassic Coast is always unveiling fresh secrets and I’d like to think that similar discoveries will continue to be made right on our doorstep,” said study co-author Dave Martill, a Professor of Palaeobiology at the University of Portsmouth, according to The Guardian.