Scientists find 74-million-year-old mammal fossil in Chile
Environment & Climate
By
AFP
| Aug 12, 2025
Scientists have discovered the fossil of a tiny mouse-sized mammal that lived in the time of the dinosaurs in Chilean Patagonia.
"Yeutherium pressor" weighed between 30 and 40 grams (about one ounce) and lived in the Upper Cretaceous period, about 74 million years ago.
It is the smallest mammal ever found in this region of South America, dating back to the era when it was part of a continental land mass known as Gondwana.
The fossil consists of "a small piece of jaw with a molar and the crown and roots of two other molars," said Hans Puschel, who led the team of scientists from the University of Chile and Chile's Millennium Nucleus research center on early mammals.
The discovery was published this month in the British scientific journal Proceedings of the Royal Society B.
READ MORE
Lamu Port roars to life as nine mega ships scheduled to call
Asal counties to benefit from Sh15b off-grid solar project
Farmers earn Sh882 million at tea auction
London forum to chart Africa's place in shifting global landscape
KTDA hydropower plant connected to the national grid
Harnessing devolution to transform agriculture
Chinese firm to revive fluorspar operations in Kerio Valley
Why counties should rethink their infrastructure financing
Port of Mombasa caught in tariff wars crossfire
Homa Bay traders make a kill as curtains fall on Devolution Conference
Researchers found the fossil in the Rio de las Las Chinas Valley in Chile's Magallanes region, about 3,000 kilometers (1,864 miles) south of Santiago.
Despites its similarity to a small rodent, "Yeutherium pressor" was a mammal that must have laid eggs, like the platypus, or carried its young in a pouch like kangaroos or opossums.
The shape of its teeth suggests that it probably had a diet of relatively hard vegetables.
Just like the dinosaurs with whom it co-existed, the tiny mammal abruptly went extinct at the end of the Cretaceous period, about 66 million years ago.