Stories tagged dinosaurs

I missed hearing about this over the summer when the film played in theaters, but finally had the chance last night to watch "Dinosaur 13," a documentary film about the legal battles in the aftermath of the discovery of Sue the T. Rex in South Dakota in 1990. Actual paleontology plays just a small role in the film, but the ethics and legalities of dinosaur hunting are very interesting. It's available now on DVD and I highly recommend it. You can preview the trailer below and here is the link to the movie's official website for streaming options:

See video

Here's a video look at fossil pieces of Dreadnoughtus, the huge sauropod dinosaur found in Argentina recently.

When I read that the Smithsonian's dinosaur hall will be shutting down for five years for remodeling, it struck me as taking an awfully long time. Then I read this story and it makes perfect sense. It takes a lot of time to clean dinosaurs.

Sep
24
2013

Big-nosed dinosaur: Nasutoceratops gets its name party from its extremely big nose.
Big-nosed dinosaur: Nasutoceratops gets its name party from its extremely big nose.Courtesy Lukas Panzann
(Psst everybody.....don't mention anything about his big nose. Got it? He's kind of sensitive about it.)

Okay, paleontologists from the University of Utah have recently discovered a new dinosaur very similar to triceratops, that has a very large...um, um, set of horns.

Roaming about present day Utah some 76 million years ago, measured about 15 feet long. Its colossal 4.5-foot skull bore a single horn over the nose, a horn above each eye and an elongated, bony frill toward the rear. Its large, flat teeth were perfect for eating plant matter.

But what really set this dinosaur apart is its extremely large...um, um, feet. Yeah that's it. This 2.5 ton dinosaur walked around great big feet.

Its horns are much more curved than Triceritops – almost looking like cattle horns – yet its frill is much more plain than its cousin's. Paleontologists have long speculated about the function of horns and frills on horned dinosaurs. Ideas have ranged from predator defense and controlling body temperature to recognizing members of the same species. But prevailing view today is that the horns primary purpose was for competing for mates.

And of course, Nasutoceratops had a huge honking schnoz on the front of its face, a nose bigger than any of its planting-eating, frilled and horned relative. (Ooops, I wasn't supposed to say that, was I.) But researchers don't think the big nose gave Nasutoceratops a more refined sense of smell. Olfactory receptors would have sat farther back in the skull, just like other dinosaurs. Like the horns, the big nose was probably a key to attracting mates.

How old does this look?: New research says parts of the Grand Canyon may be 65 million years, or so, older than originally thought.
How old does this look?: New research says parts of the Grand Canyon may be 65 million years, or so, older than originally thought.Courtesy chensiyuan
Grand Canyon, could you please show us your birth certificate? A new theory that parts of the Grand Canyon were carved as far back as dinosaur days has geologists picking sides on a controversy. New research contends that the western end of the canyon might be up to 70 million years old, carved by an ancient river that flowed in the opposite direction of today's Colorado River. Conventional theories about the canyon had its aged pegged at 5 to 6 million years old.

So what do you think?

Dec
02
2011

Rapetosaurus krausi: The Cretaceous titanosaur is dwarfed by the massive leg bones of its larger Jurassic cousin Apatosaurus. Field Museum of Natural History.
Rapetosaurus krausi: The Cretaceous titanosaur is dwarfed by the massive leg bones of its larger Jurassic cousin Apatosaurus. Field Museum of Natural History.Courtesy Mark Ryan
Paleontologist Kristina Curry Rogers, a former curator here at the Science Museum of Minnesota, has dedicated much of her career studying sauropod dinosaurs, their behaviors, and the histology of their bones. Sauropods are a diverse group of large, long-necked dinosaurs that include, among others, the popular Apatosaurus (Brontosaurus), Diplodocus, Barosaurus, and Brachiosaurus. The four-legged, herbivorous sauropods made their first appearance in the Late Triassic Period about 220 million years ago, then rose to prominence during the Late Jurassic, growing to 80 tons or more. The Jurassic giants gave way to the titanosaurs in the Cretaceous, a group that thrived until 65 million years ago when a major extinction event wiped out all the mega-fauna dinosaurs.

Osteoderms in a modern reptile: Bumps of bony armor seen embedded in the skin of a Gila Monster  (Heloderma sp.)
Osteoderms in a modern reptile: Bumps of bony armor seen embedded in the skin of a Gila Monster (Heloderma sp.)Courtesy Fritz Geller-Grimm via Wikipedia Creative Commons
Now an assistant professor at Macalester College in St. Paul, Curry Rogers' latest research centers on titanosaur osteoderms. Osteoderms are bony deposits embedded in the skin and used as defensive protection or for other functions such as temperature regulation. The bumpy armor can be seen today in alligators, crocodiles and many other reptilian forms (see photo). So far, titanosaurs are the only sauropod dinosaurs known to have had osteoderms.The smaller ornithopod dinosaurs such as ankylosaurs and stegosaurs used osteoderms to create bony exteriors to strengthen their hide against attack. On the predator side of the equation, the carnivore Ceratosaurus is the only theropod dinosaur found with osteoderms.

Curry Rogers has been studying the osteoderms of two titanosaur specimens (Rapetosaurus krausi), one from an adult and the other from an immature individual. Both specimens were found in the 1990s in the sandstones of the Maevarano Formation exposed on the northwest corner of the island of Madagascar. During the Late Cretaceous the climate in the region was seasonal with periods of rain and drought alternating with periods of semi-arid conditions.

Heads up: Rapetosaurus krausi stands before Charles R. Knight's classic rendition of its Jurassic ancestor, Apatosaurus
Heads up: Rapetosaurus krausi stands before Charles R. Knight's classic rendition of its Jurassic ancestor, ApatosaurusCourtesy Mark Ryan
That a 50-foot adult Rapetosaurus would even need osteoderms at first mystified the paleontologist. A full-grown Rapetosaurus was just too enormous to require body armor.

Using a CT scanner and core-sampling to analyze the two samples, Curry Rogers found that the juvenile osteoderm had a thick, dense outer lining on the outside and was filled with a spongy bone on the inside. The larger adult osteoderm - 22 inches in length and the largest ever found - appeared much the same from the outside but surprisingly the shell wasn’t as thick and the inside was almost completely hollow. Microscopic examination of the inside lining of the outer structure showed signs of it being resorbed into the body

The new data made the paleontologist wonder. Why would the osteoderms appear one way in an earlier life stage and change into another form in adulthood? Did their functions change as the titanosaurs passed through different stages of life?

Eventually the paleontologist came up with a hypothesis: the osteoderms were probably used as armor when the Rapetosaurus was small and still growing, and easy prey for predators. But as it neared adult size the osteoderms were no longer needed for protection and instead could have served as reservoirs for minerals, such as calcium and phosphorus. These would have been useful as the dinosaurs' size increased or when the adult titanosaurs needed extra minerals during times of environmental stress (like the frequent droughts occurring on Madagascar during the Late Cretaceous). Drawing minerals from its arm or leg bones would have weakened them making it difficult for the multi-ton animals to stand or walk. The mineral stores could also be used during reproduction when calcium was necessary for egg shell production.

Curry Rogers and her colleagues have published their findings in the online journal Nature Communications and can be downloaded here.

SOURCES and LINKS
Sauropod Dinosaur Osteoderms from the Late Cretaceous of Madagascar
Smithsonian’s Dinosaur Tracking "Inside Sauropod Armor
Star Tribune story
Macalester College news release

Why the "yee-haw," JGordon?

Man, I don't know. Because "dinosaur feathers" sounds lot like "horse feathers," and no one in the history of humanity has ever uttered "horse feathers" without also shouting "yee-haw" in the same five-minute window. And because dinosaurs and their feathers are exciting, so why not toss a little yee-haw in there.

It doesn't matter, really. What matters is that you check out all these cool images of Cretaceous period feathers preserved in amber.

Yee-haw.

There's been a whole lot of buzz on the internet recently about Brontomerus mcintoshi, a giant sauropod dinosaur with unusually large hips (and somewhat derogatory name translation) discovered more than a decade ago in eastern Utah. In this video, British paleontologist Mike Taylor explains the hows and whys of "Thunder Thighs". Hey that rhymes.

You can read even more about Brontomerus over at Taylor's Sauropod Vertebra Picture of the Week (SVPoW) blog.