A 30 million year-old fossil whale may not be the heaviest animal of all time after all, according to a new analysis by paleontologists at UC Davis and the Smithsonian Institution. The new analysis puts Perucetus colossus back in the same weight range as modern whales and smaller than the largest blue whales ever recorded. The work is published Feb. 29 in PeerJ.
We live in a geometric world. From the rectangular skylines of our cities and the orbiting planets of our solar system to the symmetry of butterfly wings and the spiraling double helix of DNA, every shape has its place.
For as long as he can remember, Ryosuke Motani has been fascinated by shapes. And he’s built an illustrious paleobiology career studying them.
For decades, Geerat Vermeij has forged an illustrious career in the sciences by studying the intricacies of ancient seashell fossils. The findings he’s gleaned from his meticulous work have yielded broader insights about evolution, humanity, biology, economics and now, the role of power. In his new book, Vermeij explores how “the history of life on Earth can be meaningfully and informatively interpreted as a history of power” with the human species representing the current apex.
Modern birds and mammals are “warm-blooded” or endothermic, maintaining a constant body temperature and generating heat internally, while reptiles rely on heat from their surroundings. It has been known for some time that at least some dinosaurs, including the direct ancestors of modern birds, were also endotherms.
Over the course of her career, Distinguished Professor Isabel Montañez has created a
research niche in the fields of geochemistry and paleoclimatology: applying an Earth
systems science approach to recreate Earth from eons past. For her monumental work
in the geology field, Montañez recently received the Geological Society of America’s
Arthur L. Day Medal.
Northeastern China is home to one of the world’s most remarkable collections of dinosaur fossils. The Jehol biota contains fossils of dinosaurs, plants, insects and fish, many of them preserved in unusual detail with traces of skin and feathers, dating back to the Early Cretaceous period 101 to 143 million years ago.
Some 240 million years ago, a dolphin-like ichthyosaur ripped to pieces and swallowed another marine reptile only a little smaller than itself. Then it almost immediately died and was fossilized, preserving the first evidence of megapredation, or a large animal preying on another large animal. The fossil, discovered in 2010 in southwestern China, is described in a paper published Aug. 20 in the journal iScience.
The ichthyosaurs were sleek, dolphin-like marine reptiles that roamed the oceans while dinosaurs ruled on land. But the earliest known member of the group was a short, seal-like animal that could likely pull itself onto land.
Now, scanning of that animal’s skull shows that it likely fed on hard-shelled animals such as shellfish and crabs. The appearance of similar teeth in other ichthyosaurs gives insight into how these animals were evolving in the wake of the mass extinction at the end of the Permian era, 250 million years ago.
About 200 million years ago, much of the life on Earth was wiped out in the end-Triassic mass extinction. The catastrophe may have been caused by climate change related to massive volcanic eruptions.
If “Why?” is the first question in science, “Why not?” must be a close second. Sometimes it’s worth thinking about why something does not exist. Such as a truly three-legged animal.
