Skip to content
The latest news from the UW

Tag: Christian Sidor

October 27, 2021

Fossil dental exams reveal how tusks first evolved

Illustration of an ancient mammal-like creature in a forest setting.

Many animals have tusks, from elephants to walruses to hyraxes. But one thing tusked animals have in common is that they’re all mammals — no known fish, reptiles or birds have them. But that was not always the case. In a study published Oct. 27 in the Proceedings of the Royal Society B, a team of paleontologists at Harvard University, the Field Museum, the University of Washington and Idaho State University traced the first tusks back to dicynodonts — ancient mammal relatives that lived before the dinosaurs.

May 21, 2021

Pandemic-era paleontology: A wayward skull, at-home fossil analyses and a first for Antarctic amphibians

An image showing a block of amphibian fossils from Early Triassic Antarctica

Researchers at the University of Washington and its Burke Museum of Natural History & Culture have discovered the first fossil evidence of an ancient amphibian, Micropholis stowi, from Antarctica. Micropholis lived in the Early Triassic, shortly after Earth’s largest mass extinction. It was previously known only from fossils in South Africa, and its presence in Antarctica has implications for how amphibians adapted to high-latitude regions in this dynamic period of Earth’s history.

Weathering the tough times: Fossil evidence of ‘hibernation-like’ state in 250-million-year-old Antarctic animal

An artist's rendition of an ancient vertebrate called Lystrosaurus

University of Washington scientists report evidence of a hibernation-like state in Lystrosaurus, an animal that lived in Antarctica during the Early Triassic, some 250 million years ago. The fossils are the oldest evidence of a hibernation-like state in a vertebrate, and indicate that torpor — a general term for hibernation and similar states in which animals temporarily lower their metabolic rate to get through a tough season — arose in vertebrates even before mammals and dinosaurs evolved.

Fossilized evidence of a tumor in a 255-million-year-old mammal forerunner

A tumor next to a tooth.

University of Washington paleontologists have discovered a benign tumor made up of miniature, tooth-like structures embedded in the jaw of an extinct ‘mammal-like’ gorgonopsian. Known as a compound odontoma, this type of tumor is common to mammals today. But this animal lived 255 million years ago, before mammals even existed.

August 13, 2015

‘Scarface,’ an ancient cousin to mammals, unearthed in Africa

Photograph of the skull of Ichibengops munyamadziensis.

A team of scientists has identified a new species of “pre-mammal” based on fossils unearthed in Zambia’s Luangwa Basin in 2009. The ancient, Dachshund-sized creature lived some 255 million years ago, in a time just before the largest mass extinction in Earth’s history. Its discoverers include Christian Sidor, professor of biology at the University of Washington and curator of vertebrate paleontology at the Burke Museum of Natural History and Culture. Sidor and his colleagues, who announced their finding in July…