Paleontologists in California announced this week that fossils excavated in the early 2000s represent four new species of ancient whales. The toothed baleen whales apparently stuck around longer than scientists once thought, and they may hold clues about how and when whales evolved from toothy giants to the baleen-equipped beasts we see today.
Sue is something of a celebrity among dinosaurs, being the best-preserved T. rex fossil ever found. But in truth, the gender of dinosaurs is rarely, if ever, known. A study in 2005 first laid claim to a new way to sex dinosaurs using a distinctive bone formation. Now paleontologists in China have found that ancient birds also had this structure, confirming that birds and dinos shared similar gender divisions and reproductive habits.
Researchers excavated the 125-million-year old birds’ feathers, organs and bones from petrified lake-bottom mud in northeastern China. These birds, called Confuciusornis sanctus, were buried by the hundreds following catastrophic volcanic eruptions in the Mesozoic era.
Paleontologists in Tanzania have unearthed fossils from a new species of prehistoric reptile. The bones may have belonged to the world’s oldest dinosaur—or they may be from a reptile that kind of looks like a dinosaur.
Currently, the oldest confirmed dinosaur fossil dates back 230 million years. By this point in time, dinosaurs had grown in size and population to dominate the Earth. But when exactly did dinosaurs first enter the prehistoric picture, and how long did it take them to rise to such prominence? Paleontologists have narrowed the timeline down to the early or middle Triassic—the period of 20 million years before the oldest known dinosaur came to be. The newfound species, dubbed Nyasasaurus parringtoni, predates this fossil by another 10 to 15 million years, and falls right in the middle of paleontologists’ projected timeframe for the first appearance of dinosaurs.
Paleontologists now think they know how the predatory Tyrannosaur ate the well-protected Triceratops: by ripping its head off. The carnivore may have forcefully yanked on the bony frills around the neck of its horned prey in order to get to the rich meat beneath. The researchers, who reported their findings at the Society of Vertebrate Paleontology’s annual meeting last week, suggested this scenario after examining Triceratops skulls, where they found puncture and pull marks on the neck frills—along with bite marks on the head-neck joint that could only have been made on a severed head.
For a fuller explanation, replete with step-by-step illustrations, visit Nature News.
Drawing courtesy of Nate Carroll via Nature
It’s always nice to put a face to a name—and not just in the case of humans. Paleontologist Paul Sereno just introduced the world to Pegomastax africanus, a small two-legged dinosaur that lived 200 million years ago, traipsing through what is now South Africa armed with a pointed beak, unexpectedly sharp canine teeth, and a bristling coat of quills. Calling to mind an image of such an unusual animal is difficult (I come up with a sort of parrot-wolf-porcupine-raptor mix which, while intriguing, is certainly not correct). Luckily, however, there are people like Tyler Keillor, a paleoartist who builds lifelike models of ancient animals, letting us see them face to face rather than as a list of features. In the video above, he reconstructs P. africanus layer by layer, starting with a resin skull and adding clay muscles, all the way up intricately painted silicone rubber skin and fishing-line quills.
[via Scientific American]
Sprechen ze deutsch?
This poem in praise of the Permian amphibian Eryops was scrawled on the back of a label now in the American Museum of Natural History by Jacob Boll, a Swiss-German fossil hunter involved in a tumultuous 19th-century paleontology feud.
Birds are the modern descendants of dinosaurs, but the exact details of the family tree are controversial. Archaeopteryx, the winged creature found in German fossil beds whose name means “first from a feather,” was long thought to be the first bird. Last summer, a Nature paper by Xu Xing, of China’s Institute of Vertebrate Paleontology and Paleoanthropology, claimed that Archaeopteryx was related to birds but actually belonged on a separate branch of the tree, with other bird-like dinosaurs.
Scientists still debate the rightful place of Archaeopteryx in the dinosaur-bird lineage, but what’s undisputed are Xu’s contributions to paleontology. He has named 60 dinosaur species, more than any other living paleontologist, and his stamping grounds are the fossil beds of Liaoning Province, northeast of Beijing, where many of the feathered dinosaurs and early birds were discovered. Kerri Smith enumerates Xu Xing’s contributions to the study of birds and their dinosaur relatives in a profile at Nature News: Read More
A 230-million-year-old mite preserved in amber
An insect trapped in amber, perfectly preserved for millions of years: the image is familiar to fans of Jurassic Park, but in fact, few insects got stuck in sticky tree resin until about 130 million years ago—long after the Jurassic period ended. That’s when trees first began to produce enough of it to ensnare flies and mites.
Or so paleontologists believed. Three newly discovered bugs in amber may force a revision of that timeline. As a new study reports in Proceedings of the National Academy of Sciences, these specimens are 230 million years old.
One hundred and twenty million years ago, this fearsome creature roamed the skies above China. This recently discovered skull is the first evidence of this species of pterosaur (a flying reptile, not a dinosaur) that scientists have found, though similar fossils have been unearthed halfway around the world in Brazil. The new species name, Guidraco venator, is a portmanteau of Chinese and Latin words together meaning “ghost dragon hunter.” Those dramatic teeth have got scientists talking about how the heck it ate: did it hunt actively for the fish whose bones are in those clumps of poop (“copr” stands for “coprolite“) scattered around it, or did it scavenge? Either way, it looks like a creature that gets whatever it wants, when it wants it.
Above, the fossilized teeth running along the katydid’s left and right wings
that researchers used to reconstruct the creature’s call.
Well-preserved fossils can tell paleontologists myriad things, such as what color feathers dinosaurs had, how ancient spiders evolved, and what kind of microbes were around 3 billion years ago. The latest such revelation is rather whimsical, as well as being scientifically interesting. Scientists have been able to reconstruct the chirping of a Jurassic ancestor of modern katydids by examining the wings of an exquisitely preserved fossil specimen.
Katydids create their song by scraping one wing across the other, running a hard ridge of tiny teeth, like those on a comb, across the ridge on the opposite wing. The research team examined the size and shape of the teeth on the wings of Archaboilus musicus, as the Jurassic specimen is called, to come up with an estimate of the frequency of the sound that such scraping would have produced. They found that the resulting chirping would have fallen at 6.4 kilohertz, within the range of normal human hearing.
So, if you ever get the chance to travel back 165 million years, keep your ears pricked. You might hear something that sounds like this:
Image and video courtesy of Gu et al, PNAS