Taxonomy term

mammal

Growing up saber-toothed: Strong from the start

During the Pleistocene, saber-toothed cats were formidable predators, with their massive canines and powerful front legs sporting razor-sharp claws. The bones of saber-toothed cats are thicker and more robust compared to those of other large cats, both modern and extinct. And previous studies of Smilodon have shown that their forelimbs in particular featured several adaptations, including thickened cortical bone, which would have increased strength, presumably useful in subduing ambushed prey.

19 Feb 2018

Down to Earth With: Paleontologist Ali Nabavizadeh

A perfect day in the life of paleontologist Ali Nabavizadeh wouldn’t be complete without a fresh corpse. The subjects of his work at the dissection table range from a rhinoceros, to an elephant head, to the human cadavers essential to the anatomy classes he teaches at Cooper Medical School of Rowan University in Camden, N.J. The only thing that could possibly top a fresh corpse, in fact, is an extremely old one.

20 Dec 2017

End of ice age may have been too wet for megafauna

Between 15,000 and 11,000 years ago, dozens of ice-age megafauna species went extinct. Various causes, from climate-driven habitat changes to overhunting to extraterrestrial impacts, have been cited for these extinctions. But new research looking at fossils of large herbivores such as bison, horses and llama supports the idea that a worldwide uptick in moisture was a main driver of the extinction trend.

08 Sep 2017

Bipedalism left its mark on human skull: Kangaroos and upright rodents show same signs

The transition to bipedal walking in our ancestors changed the hominin skeleton in many ways. New research looking at how upright walking affected the structures at the base of the skull in both early humans and other bipedal mammals, like kangaroos, is shedding light on a once-controversial marker for bipedalism.

04 Jul 2017

Horses evolved to get along: Competition between species not main evolutionary driver

Horses have changed size and shape dramatically over the last 20 million years, evolving from small dog-sized creatures with multiple toes into the large, hoofed grazing animals we see today. But the factors that drove these changes have been unclear. In a new study in Science, scientists tested the long-held theory that horses evolved rapidly to compete with one another during the worldwide expansion of grasslands starting 18 million years ago.

07 Jun 2017

Tiny dinosaur-era marsupial packed a big bite

Newly described fossils from one of the earliest-known marsupials are shedding light on the evolution of mammals during the Mesozoic and revealing an animal with an impressive bite, perhaps strong enough to take down a dinosaur.

19 Apr 2017

Extinct tiger had unique elbow, hunting style

During the Pleistocene, the marsupial lion, Thylacoleo carnifex, was one of Australia’s top predators. Fossil records indicate the jaguar-sized cat died out between 20,000 and 10,000 years ago (although rumors persist the “Queensland Tiger” may still survive in isolated habitats). In a new study examining Thylacoleo fossils, researchers have now found an elbow joint unique among living predatory mammals.

16 Dec 2016

Tiny bones pull India into the story of early primate evolution

Bones of an ancient rat-sized, tree-dwelling primate have recently been discovered in a coal mine in Gujarat, India, and may represent the most primitive known remnants of the divergence between the two great primate clades.

07 Dec 2016

Humans, megafauna coexisted in Patagonia before extinction

During the last ice age, giant mammals roamed the wide-open steppes of what is now Patagonia. Around the time that humans were making their way down through North America and into South America, the climate began warming and large species of giant sloths and saber-toothed cats soon disappeared. Now, researchers looking at mitochondrial DNA from some of these megafaunal species are shedding light on the timing of the extinction and whether encroaching humans or changing climate — or both — were to blame for their disappearance.

11 Oct 2016

Mammals hit harder than thought by end-Cretaceous extinction

Mammals, unlike the remaining nonavian dinosaurs and many other animals, are thought to have fared relatively well through the massive meteorite impact and protracted volcanism at the end of the Cretaceous 66 million years ago. After the extinction, mammals went on to dominate terrestrial ecosystems. But new research indicates that mammals might have taken a bigger hit than paleontologists have realized: Instead of about 75 to 85 percent of species going extinct, as prior studies suggested, it looks like about 93 percent of all mammal species may have gone extinct during the Cretaceous-Paleogene (K-Pg) extinction.

05 Oct 2016

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