This Week: Ancient water = ancient habitat?
In the News: Accidents: Why Do They Happen?
Classroom Activity Page: The fossil of a plesiosaur, which was a large, dangerous predator of the seas between 200 and 85 million years ago, showed strong evidence of being pregnant. Evidence for pregnancy included the location of the unborn plesiosaur, its size, and the fact that its bones were not fully hardened, or ossified. The find helps flesh out the evolutionary transition between laying eggs and live birth.
78 million years ago, a pregnant predator of the Cretaceous ocean died and sank to the sea floor. Today, her fossil gives the first proof that plesiosaurs, one of the commonest and baddest marine reptiles of the era, did not lay eggs. It gave birth.
Darwin thought life had to predate the Cambrian era, and yet there was no evidence. In 1953, a Wisconsin geologist saw fossils aged almost 2 billion years. Now, life has been discovered in rocks from 3.5 billion years. What was life like, and how do we recognize it?
It’s one of the biggest puzzles of paleontology: Why did North America’s large mammals go extinct shortly after the glaciers melted about 15k years ago? New study suggests that hunters get the credit — or blame.
220-million-year-old rock reveals four-legged reptile with wings. Fossils could not be removed, so the images came from CT scanner.
Just after humans reached the Western Hemisphere, many large mammals went extinct. Some scientists have blamed hyper-effective human hunting. But a new study fingers changes in climate and environment.
This CSI is a picture of a pollen grain from an extinct group known as triprojectates. This particular beast, Triprojectus unicus, was common about 65 million years ago in the Late Cretaceous, when the dinosaurs still ruled the roost. The nasty-looking recurved spines may have allowed the pollen grains to hitch rides on passing insects. [...]
How amber is used in archeology and paleontology: Reviving ancient bacteria, viewing ancient insects, what’s not to love about amber?