dinosaurs

Our knowledge of the evolution of feathers in dinosaurs is sketchy, at best, but new research on fossilized feathers is painting a remarkably clear picture of what one species, known as Microraptor, may have looked like — a raven with black iridescent feathers. The findings may have implications for the importance of sexual display in the early origins of feathers.

“This is the way it was.” Or: “This is what is happening.” Hmmm. Scientists don’t usually make such definitive statements, given that in science, there are almost always caveats. Yet in the last year, such statements have been issued by several large groups of scientists who have come together to support a certain point of view. Are scientists feeling the need to dig in their heels because of public pressures? Or are we actually reaching some consensus?

What's commonly thought of as the first bird, Archaeopteryx was first described 150 years ago this month.

Ask a third grader what happened to the dinosaurs and she will tell you that an asteroid killed them all. Many adults even know what caused the demise of the dinosaurs: A massive bolide crashed into the Yucatán Peninsula in Mexico about 65 million years ago, setting in motion a series of environmental changes that killed off 60 percent of life on Earth. But if you ask people about the origin of dinosaurs 165 million years earlier, you get blank looks. Even many paleontologists have little to say about the subject.

Triceratops and its cousin Torosaurus are not hard to tell apart. Both horned dinosaurs had a giant bony frill that rose up behind the head, but Torosaurus’ frill was much longer and was adorned with giant holes that were covered by a thin layer of protein called keratin. Yet Triceratops and Torosaurus may have been more alike than scientists realized: New research suggests that the two animals were actually the same species, with Torosaurus being the adult version of Triceratops.

The revolution started with a bang in 1980. For some, this revolution became a religion, even an orthodoxy. The true believers became proselytes and began to see signs supporting their viewpoint everywhere. But each time the proselytes claimed to have found yet another example in support of their “religion,” naysayers and doubters emerged. Two sides formed, each loudly castigating and questioning their opponents.

This back-and-forth ideological debate describes both the historical and still-ongoing struggle over a purported cause of mass extinctions: the meteor impact theory.

About 18 million years earlier than they were thought to exist, tetrapods — vertebrates with four limbs instead of fins — walked in what is today Poland. A new study published in Nature describes tracks belonging to a tetrapod in a Polish tidal flat, dating to the Middle Devonian period, about 395 million years ago. The discovery may prompt scientists to completely reassess the environment, origins and timing of early tetrapods.

Whether dinosaurs were warm-blooded or cold-blooded has been a long-standing question in paleobiology. Now, new research on how two-legged dinosaurs walked and ran adds new evidence to the argument for warm-bloodedness, and suggests that even the earliest dinosaurs may have been warm-blooded.

In 1861, German paleontologist Christian Erich Hermann von Mayer excavated the fine-grained limestone layers of a quarry near Solnhofen, Germany. The 150-million-year-old limestone had already proven promising for finding fossils: A year earlier, von Mayer had found the imprint of a single feather preserved in the rock. But this time, he discovered something more spectacular: an entire skeleton of what appeared to be an ancient bird.

The Tyrannosaurus rex — arguably the most famous dinosaur of all time — was also one of the most efficient predators to ever walk on Earth. With its powerful jaws, large eyes, strong hind limbs and even tiny arms, the T. rex was uniquely designed to swiftly run down and dispatch prey. But on Wednesday, scientists announced that those characteristic T. rex features were not as unique as once thought: A new fossil find shows that 60 million years earlier, a T.

Lillian the Albertosaur strolls through the halls of the American Museum of Natural History in New York City, glancing sideways at the skeletal model of a T. rex. She’s much prettier than the skeleton, from her textured brown skin, adorned with bright purple spots, to her slightly superior smirk. Neither dinosaur is actually alive: One is a fossil, and the other is a computer graphic superimposed on a photograph of the actual museum. But somehow, Lillian does liven the place up.

What the planet’s past mass extinctions tell us about the future of life on Earth

The crash-landing of a 10-kilometer-wide asteroid 65 million years ago made for a very bad day for dinosaurs — or one very lucky day for mammals.

A two-year-old debate is back in the flesh — literally.

Molecular paleontologist Mary Schweitzer of North Carolina State University in Raleigh and colleagues presented evidence this week in Science that they had successfully recovered and identified collagen, a type of protein, from the femur of an 80-million-year-old hadrosaur, a duck-billed dinosaur.

Or so a new fossil discovery might indicate.

Paleontologists have puzzled over the lambeosaur, an odd-looking duck-billed dinosaur, since its fossils were discovered in 1914. In particular, scientists were curious about the distinctive crest on the lambeosaur’s head: Elongated and complex nasal passages led air from the dinosaur’s nostrils up into the hollow crest and back down into its lungs. But what purpose these nasal passages served was a mystery — until now.

Fossilized feces reveal significant details about ancient life

How often do you laugh when you talk to a scientist? Over the years, I have interviewed and talked with dozens of geologists, biologists and archaeologists. I often come away feeling the researcher’s passion and excitement about his or her subject, but rarely do I come away with a sense of mirth, until I started to talk to people who work with coprolites. I don’t mean to imply that the researchers aren’t serious about their work — they are. But they also exude a healthy sense of humor.