Researchers led by the University of Washington studied a fossil found in 2009 at a research site in Baja California. The team recovered teeth, a skull, jaws and parts of the skeleton, including a femur and an ulna.
The scientists named the new species Cimolodon desosai. It lived on the Pacific Coast about 75 million years ago and was about the size of a golden hamster. Researchers say it likely scampered on the ground and climbed trees and that it ate fruits and insects.
The species is part of the multituberculate group, animals that first appeared in the Jurassic and survived for more than 100 million years before going extinct.
Difficult words
- fossil — remains of a plant or animal in rock
- recover — find and bring back from a siterecovered
- species — group of similar living organisms
- extinct — no longer living anywhere on Earth
- femur — thigh bone in many animals
- multituberculate — an early group of extinct mammals
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Would you like to see this fossil in a museum? Why?
- Do you think this animal lived more on the ground or in trees? Give one reason from the text.
- Which found part (teeth, skull, femur, ulna) interests you most? Why?
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