66 million years ago, the last dinosaurs vanished from Earth. We're still trying to understand why. New fossils of abelisaurs—distant relatives of the tyrannosaurs—from north Africa suggest that African dinosaurs remained diverse up to the very end. And that suggests their demise came suddenly, with the impact of a giant asteroid.

The causes of the mass extinction have been debated for two centuries. Georges Cuvier, the father of paleontology, thought extinction was driven by catastrophes. Charles Darwin thought gradual changes in the environment and competition between species slowly drove lineages extinct.

Paleontology enthusiasts have unearthed one of the world's richest and most diverse fossil sites from the Lower Ordovician period (around 470 million years ago). Located in Montagne Noire, in the Hérault department of France, this deposit of over 400 fossils is distinguished by an exceptionally well-preserved fauna.

In addition to shelly components, it contains extremely rare soft elements such as digestive systems and cuticles, in a remarkable state of preservation. Moreover, this biota was once located very close to the South Pole, revealing the composition of Ordovician southernmost ecosystems.

The prehistoric animal kingdom was a riot of colors, from iridescent-feathered dinosaurs to jet-black ink excreted by Jurassic squid relatives. Like modern-day animals, ancient species' hues helped them communicate, camouflage and even regulate body temperature. But reconstructing these colors today is a challenge because compounds and structures that color animals' skin, fur and feathers usually degrade or change during fossilization. Experts have developed methods to reliably detect structures and pigments related to dark colors like the black and brown of feathered dinosaurs, but other shades (like the yellow and reddish-orange made by pigments called pheomelanins) have been especially hard to pin down.

Now a team of scientists has filled in that missing chunk of the prehistoric palette by developing the first reliable test to detect these gingery colors in fossils. “Pheomelanin is clearly an elusive pigment, and these findings will absolutely help us to detect evidence of ginger pigments in other fossils,” says the study's lead author Tiffany Slater, a paleobiologist at University College Cork in Ireland. The results were recently published in Nature Communications.

Researchers have identified a newfound sauropod species that was the largest of its kind and one of the last living members of its family.

Paleontologists first discovered fossils from the species, now named Sidersaura marae, in 2012 in the Huincul Formation in Argentina's Neuquén Province. It took researchers multiple excavations over several years to retrieve the giant dinosaur parts, which came from four individuals, according to a study published Jan. 3 in the journal Historical Biology.

What are the origins of wings and tails in birds? This is one of the key questions in the evolution of animals. It has long been accepted that their evolution began in feathered dinosaurs.

Some of these dinosaurs had feathers on the tails and small wing-like feathers on their forelimbs. These small wing-like structures called 'proto-wings' are composed of special feathers known as pennaceous feathers—the stiff feathers found in the wings and tails of birds.

The ancient form of these feathers first emerged in dinosaurs during the Jurassic Period, and these dinosaurs, called Pennaraptorans, had proto-wings made of pennaceous feathers. However, it has been known that these proto-wings were too small for powered flight. Because we cannot time-travel to observe their behavior, what dinosaurs did and how they behaved remains unanswered.

Various functions of proto-wings and tail feathers in the ancestors of birds have been considered since John Harold Ostrom proposed the first idea 50 years ago that proto-wings were used to knock down insect prey by small predatory dinosaurs living on the ground and following their prey. However, how the small 'proto-wings' and feathered tails helped the dinosaurian ancestors of birds in their lives has not been resolved.

In the late 1970s, debate began about whether dinosaurs were at their peak or in decline before their big extinction. Scientists at that time noted that while dinosaur diversity seemed to have increased in the geologic stage that spanned 83.6 million to 71.2 million years ago, the number of species on the scene seemed to decrease during the last few million years of the Cretaceous. Some researchers have interpreted this pattern to mean that the asteroid that struck the Gulf of Mexico was simply the final blow for an already vulnerable group of animals.

However, others have argued that what looks like a decrease in the diversity of dinosaurs may be an artifact of how hard it is to accurately count them. Fossil formations might preserve different dinosaurs more or less often based on factors like their favored environment and how easily their bodies fossilized there. The accessibility of various outcrops could influence what kinds of fossils researchers have so far found. These biases are a problem because fossils are what paleontologists must rely on to conclusively answer how healthy dinosaur populations were when the asteroid hit.

Gliding winged-reptiles were among the ancient crocodile residents of the Mendip Hills in Somerset, researchers at the University of Bristol have revealed.

Kuehneosaurs looked like lizards, but were more closely related to the ancestors of crocodilians and dinosaurs. They were small animals that could fit neatly on the palm of a hand, and there were two species, one with extensive wings, the other with shorter wings, made from a layer of skin stretched over their elongated side ribs, which allowed them to swoop from tree to tree.

A new species of tyrannosaur from southern North America that may the closest known relative of Tyrannosaurus rex is described in a study published in Scientific Reports.

Sebastian Dalman and colleagues identified the new species—which they have named Tyrannosaurus mcraeensis—by examining a fossilized partial skull, which was previously discovered in the Hall Lake Formation, New Mexico, U.S.

Although these remains were initially assigned to T. rex and are comparable in size to those of T. rex (which was up to 12 meters long), the authors propose that they belong to a new species due to the presence of multiple subtle differences in the shape of, and joins between, the skull bones of the specimen and T. rex.

A new research paper published in Biology Letters has revealed that picrodontids—an extinct family of placental mammals that lived several million years after the extinction of the dinosaurs—are not primates as previously believed.

The paper—co-authored by Jordan Crowell, an Anthropology Ph.D. candidate at the CUNY Graduate Center; Stephen Chester, an Associate Professor of Anthropology at Brooklyn College and the Graduate Center; and John Wible, Curator of Mammals at the Carnegie Museum of Natural History—is significant in that it settled a paleontological debate that has been brewing for over 100 years while helping to paint a more clear picture of primate evolution.

For the last 50 years, paleontologists have believed picrodontids, which were no larger than a mouse and likely ate foods such as fruit, nectar, and pollen, were primates, based on features of their teeth that they share with living primates. But by using modern CT scan technology to analyze the only known preserved picrodontid skull in Brooklyn College's Mammalian Evolutionary Morphology Laboratory, Crowell, the lead author on the paper, worked with Chester, the paper's senior author, and Wible to determine they are not closely related to primates at all.