PALEO

paleo

Hallucigenia finally finds a home

A fossil so bizarre that it was formally dubbed Hallucigenia has finally found a place in the evolutionary tree of early life. One of the more head-scratching fossils to come out of the famous 500-million-year-old Burgess Shale assemblage in British Columbia, the worm-like creature with legs, spikes and a head difficult to distinguish from its tail was originally drawn both backwards and upside down: The spines were originally thought to be legs, and its legs were thought to be tentacles.

02 Jan 2015

All dinosaurs may have had feathers

Since the first feathered dinosaur was discovered in China in 1996, more and more feathered theropod specimens have been found. Now, a new nontheropod fossil found in Siberia and described in Science suggests that all species of dinosaurs may have had feathers.

01 Jan 2015

Oldest-known skeletal animals found

The Ediacaran Period, which lasted from 635 million to 541 million years ago, is famous for the evolution of soft-bodied organisms that pre-dated the Cambrian Explosion, the relatively brief period during which most of the major animal phyla appeared. Now, Ediacaran-aged animals with skeletons have been found.

29 Dec 2014

Limited ranges left ammonites vulnerable to extinction

Why spiral-shelled, ocean-faring ammonites went extinct at the end of the Cretaceous while the nautilids — the ammonites’ less abundant and less diverse cephalopod relatives — survived has long puzzled paleontologists. Nautilids tended to dwell deeper in the ocean than ammonites, perhaps keeping them farther out of harm’s way after the asteroid struck, which likely led to acidification of the ocean surface. Now, a new study suggests that the animals’ geographic range may have contributed to which ones lived and which ones died.

13 Dec 2014

Polar dino tracks show full ecosystem

Researchers recently uncovered a new dinosaur tracksite in Alaska’s Denali National Park. The well-preserved Late Cretaceous footprints were left by duck-billed dinosaurs called hadrosaurs. Most of the tracks are incredibly detailed, and some even show some skin impressions; they represent animals of various ages. Given the wealth of data, the tracks provide insight into the herd dynamics and paleobiology of the greenhouse-world Arctic.

28 Nov 2014

Down to Earth With: Molecular biologist Sarah L. Anzick

In May 1968, when Sarah L. Anzick was 2 years old, the 12,600-year-old remains of a male toddler were discovered at the base of a bluff on her family’s ranch near Wilsall, Mont. The Anzick infant — one of just a handful of ancient skeletons to have been found in North America and the only known Clovis burial site —  had been carefully buried with more than 100 stone and bone tools.

28 Oct 2014

Out of Africa, time and again

There is widespread agreement among scientists based on fossil and geochemical evidence that modern humans evolved in Africa between 200,000 and 100,000 years ago before spreading around the world. But the timing and route of this dispersal, and whether it occurred as a single exodus or in multiple pulses, remain contested. Now, a new study throws its weight behind a multiple-dispersal hypothesis, suggesting a first group of modern humans left Africa as early as 130,000 years ago, followed by a second about 80,000 years later.

27 Sep 2014

Ancient shark jaws resemble those of modern fish

Sharks are thought to have one of the most consistent body plans in the animal kingdom; the formidable predators seem to have remained roughly the same for more than 400 million years. But a new study, published in Nature, suggests that sharks are not the unchanging, “living fossils” that paleontologists once thought.
 

07 Sep 2014

Geomedia: 'Dinosaur 13' chisels away at the story behind discovery of Sue

The famous Tyrannosaurus rex "Sue" made headlines in the early 1990s, not only for being the most complete T. rex skeleton ever found, but also for the human drama that unfolded after the discovery. The story is the focus of a new documentary, "Dinosaur 13."

15 Aug 2014

La Brea climate adaptation as different as cats and dogs

The La Brea tar pits are famous for being a predator trap. For every herbivore, a dozen or more carnivores are pulled from the prolific Pleistocene fossil site in downtown Los Angeles. Two new studies focusing on the two most common species found at the tar pits — dire wolves and saber-toothed cats — are characterizing how the tar pits’ two top predators coped with the warming climate toward the end of the last ice age, and the results are surprisingly dissimilar: While the wolves got smaller, the cats got bigger.

12 Aug 2014

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