Stories tagged dinosaurs

Bone Wars lithograph of Stegosaurus remains: One of the many lithographs produced under the direction of Yale paleontologist O. C. Marsh during the infamous late-19th century "Bone Wars".
Bone Wars lithograph of Stegosaurus remains: One of the many lithographs produced under the direction of Yale paleontologist O. C. Marsh during the infamous late-19th century "Bone Wars".Courtesy Mark Ryan
As I've admitted before in these pages, I'm a big, big fan of the history of paleontology, especially that involving the infamous "Bone Wars" that took place in the American West during the 19th century. So I was real happy to hear that PBS is running a segment on its American Experience series tonight titled Dinosaur Wars. It's all about that legendary feud between paleontologists Othniel Marsh and Edward Drinker Cope. Several of the dinosaurs seen here at the Science Museum of Minnesota (and elsewhere) were first discovered and named by these two scientists as they raced to outdo each other in collecting and naming fossils. The show is scheduled for 8pm tonight (here in the Twin Cities), but as usual check your local listings for exact times in your area. If you can't wait until then or can't watch tonight, Rebecca Hunt-Foster over at Dinochick Blogs, gives a nice, lengthy synopsis of the program's content.

LINK
PBS Dinosaur Wars page

It's Friday, so you know the drill: time for a new Science Friday video. Science Friday
Science Friday
Courtesy Science Friday
This week,
"Reporting in the journal Science, Paul Sereno, Ricardo Martinez and colleagues describe Eodromaeus murphi. This dinosaur was four feet long, fifteen pounds and lived 230 million-years-ago, just a few million years after dinosaurs first evolved. It looks similar to its contemporary Eoraptor, except for its long canine teeth, suggesting the newly-discovered dinosaur is an ancestor of the predatory dinosaurs, including T. rex.
It's Friday, so it's time for a new Science Friday video. Science Friday
Science Friday
Courtesy Science Friday
This week...
"Reporting in the Proceedings of the National Academy of Sciences, researchers describe a new predatory dinosaur from the late Cretaceous period in Europe. Balaur bondoc (Romanian for "stocky dragon") is huskier than its closest relative the Velociraptor and has unusual feet."
Mar
20
2010

Dino killer
Dino killerCourtesy Donald Davis (for NASA)

How Earth impact kills dinos

As "mdr" explained recently in, astroid found guilty of killing dinosaurs that a panel of scientists, after reviewing all evidence, blame an asteroid impact for the demise of the dinosaurs.

Ozone killed the dinosaurs

A paper has just been published saying that dinosaurs choked on ozone.

A new study in the journal Paleogeography, Paleoclimatology, Paleoecology puts forth the idea that the Chicxulub impact, long blamed for the extinction of the dinosaurs at the end of the Cretaceous era 65 million years ago, could have done them in by flinging huge amounts of ozone precursor chemicals -- nitrogen oxides, methane, and other hydrocarbons -- into the air.

Below the article in Discovery News, this comment by 1sang (Doug) explains why mammals and avians survived.

In order to (survive) all you'd have to do is get on steeper slopes and find enough food to live for a couple of years. Mammals and smaller avian dinosaurs could more easily accomplish this than their massive cousins (in fact, many were probably already in this safety zone away from the many large predators roaming the lowlands).

He also notes that methane release leads to an increase in ozone and that today we have the beginnings of lots of methane being released (I wrote about this here: Methane ice).

Nov
20
2009

Of course, some dinosaurs may not be missing--just hiding.: Many species adopt camouflage to blend in to their environments.
Of course, some dinosaurs may not be missing--just hiding.: Many species adopt camouflage to blend in to their environments.Courtesy Elston

Looooooong time passing....

Seems like some of them were never here to begin with. Over the years, scientists have named about 700 different species of dinosaurs. But a recent study indicates that perhaps as many as a third of these were phantoms—specimens that were given distinct names despite actually belonging to another, well-known species.

For example, Torosaurus is now thought to be just a fully mature version of Triceratops. At the other end of the age scale, Nanotyrannus is considered by some to be just a juvenile form of the famous Tyrannosaurus rex.

Why the changes? Well, identifying species is hard, even under the best of circumstances. With fossils, it’s especially tricky. You often only have one specimen to study, not dozens or hundreds as with living creatures. You can only see the fossil’s bones, not the full creature. And, most important, you only have the dead body—you can’t watch the living creature to see how it changes as it grows. (Dinosaur bones, it seems, are extremely malleable and prone to change shape as the creature matures.)

But don’t be too hard on the poor paleontologists. Other scientists have this same problem. Last year, it was reported that over 30% of all living marine creatures had been misidentified, and for the same reasons. An individual (or small group) was slightly larger than normal, or slightly smaller, or a slightly different color, or came from a different location—enough to lead the scientist to classify it as a new species, when in fact it was already a member of an established species. If taxonomists can make that many mistakes with living creatures, we shouldn’t be surprised that the dinosaur family tree will need a little pruning.

Sep
10
2009

Pshhhheeeewww!: Science everywhere!
Pshhhheeeewww!: Science everywhere!Courtesy SiamEye
I don’t even know where to begin today! All I can think is “OMG!!!!” And each exclamation point I think is like a blood vessel bursting in my brain!

OMG pop pop pop

So why is this a day of excitement, instead of quiet family tragedy? Because the biggest explosions today aren’t happening in little tubes in my head, they’re happening in the world of science! (I don’t consider the physiology of my head to be science. More like magic. Or trial and error.) I just don’t know what to do with all this science.

See, unlike your average Friday Extravaganza, a Thursday Explosion has no focus; it’s just kind of all over the place. A mess! There are all these stories, but we really have to stretch to fit them into a single post… so the loose theme of this explosion will, fittingly, be “flying things.” Am I not helping? Just wait, you’ll see.

Normal mouse becomes flying mouse, doesn’t care!
Check it out: a baby mouse was put into a little chamber and subjected to an intense magnetic field. What happened? All the water in the mouse’s body was levitated. And because those squishy little mice are so full of water, the mouse itself levitated along with the water.

Unfortunately, the first mouse wasn’t quite ready for life as an aviator, and upon levitation, he began to, as scientists say, “flip his Schmidt.” Lil’ mousey started kicking, and spinning, and with minimal resistance in the chamber, he started spinning faster and faster. He was removed from the machine, and put wherever little mice go to relax. Subsequent floating mice were given a mild sedative before flying (pretty much the same thing my mom does), and they seemed cool with it. Now and again the floating mice would drift out of the region of the magnetic field, but upon falling back into it they’d float right back up. After remaining in a levitating state for several hours, the mice got used to it, and even ate and drank normally. Afterwards, the mice had no apparent ill-effects from the experiment (rats had previously been made to live in non-levitating magnetic fields for 10 weeks, and they seemed fine too.)

Aside from the excitement normally associated with floating mice, the experiment is promising in that it may be a useful way to study the effects of long term exposure to microgravity without bringing a subject to space.
pop pop pop

Great tits are dangerous if you’re a sleepy bat!

It’s true! Forget everything you thought you knew about great tits and get schooled once again, my friends, for great tits are killers!

I’m not talking about the senseless murder of bugs, either—everybody already knew that great tits are primarily insectivores. A population of great tits in Hungary have been observed hunting bats!

As fun as it is to keep writing “great tits” with no explanation, I suppose we should be clear that great tits are a type of song bird common in Europe and Asia. Little, bat-hunting songbirds.

Meat eating great tits had been reported in other parts of Europe, but it was thought that those individuals had only consumed already-dead animals. The tits of Hungary were actually observed flying into bat caves, where they would capture tiny, hibernating pipistrelle bats and drag them out of the cave to devour them alive. It even appeared that the birds had learned to listen for the bats’ disturbed squeaking (or, as I like to think of it, their horrified shrieking)—when the same noise (which is too high for humans to hear) was played back for captured tits, 80% of the birds became interested (read: bloodthirsty) at the sound.

If it really is just the Hungarian population that engages in this behavior, the situation also brings up the possibility of culture in the birds. That is, if this isn’t some sort of innate behavior, but something learned and taught, and passed through generations that way, it could be considered culture. Amazing! Great tits are cultured!

pop pop pop

Flying velociraptors!

Well, not so much flying as falling. But falling with purpose. (What was it Buzz Lightyear said? Oh yeah, “I’m so lonely all the time.”)

We all know about how awesome raptors are. I think it’s part of kindergarten curriculum now, just between how not to accidentally poison yourself, and why you shouldn’t swear and hit. Well, I remember reading a news item a couple years ago about how some paleontologists were thinking that raptors’ famous giant toe claws may not have been for disemboweling their prey. Instead, the scientists proposed, raptors would lodge the massive claw into the skin of their prey with a kick, and then use it to hang on to the unlucky animal while the raptor went bite-crazy. The researchers had made a simulation of a raptor claw, and found that it could easily puncture thick skin and flesh, it didn’t seem to be sharp enough to actually cut the skin. (Cutting is necessary for a good disemboweling.) One might argue over the strength and sharpness of raptor claws, considering that the fossilized bone claws we see in museums would have been covered with a tough, horny substance, which did not fossilize, but whatever—the new scenario was still pretty cool.

Now, the same group of paleontologists is proposing that raptor claws were also well suited to tree climbing. Raptors could have waited on overhanging limbs, and then pounced on their prey from above. Pretty neat! The researchers point out that the microraptor a tiny relative of the velociraptor, had feathered limbs to help it glide down from high places, so it’s not a stretch to think that its cousins were comfortable in trees too. “The leg and tail musculature,” one scientist says, “show that these animals are adapted for climbing rather than running.”

I’ll take his word for it, I guess, but I do have some questions on that point. There’s a dromaeosaur (it looks a lot like a velociraptor) skeleton here at the museum, and I seem to remember that its tale was supposed to be very stiff—it has these cartilage rods running the length of the tail to keep it rigid. I feel like a long, stiff tail would be a pain in the butt up in a tree. It’s not the sort of thing arboreal animals invest in these days. Also, I wonder what sort of vegetation was around in the areas raptors lived. Plenty of big trees with good, raptor-supporting limbs? (I’m not implying that there weren’t, I’m just curious.)

The researchers do acknowledge that tree climbing wouldn’t have been every raptor’s cup of tea, however. Species like the utahraptor, weighing many hundreds of pounds, and measuring about 20 feet in length would have been “hard put to find a tree they could climb.”

pop pop pop

Pretty neat stuff, huh? Explosions usually are. But you see now why I couldn’t wait for three posts to get it all out there.

Aug
26
2009

Not, in fact, a dinosaur: But still interesting.
Not, in fact, a dinosaur: But still interesting.Courtesy Ryan Somma
The Telegraph, the only newspaper brave enough to bring us stories about lost monkeys, unusual looking cats, and the daily trials and tribulations of British pensioners, is one of my favorites. I mean, I’m not going to read about giraffe penis mixups in so called “real” newspapers.

That’s why it's so painful for me to read, in an otherwise intellectually impeccable publication, headlines like this:

Dinosaurs hit rivals like athletes hit balls:
Glyptodont dinosaurs had a finely-adapted tail with a "sweet spot" which clubbed rivals in the same way as tennis or cricket players hit balls, scientists say.

Do you see the trouble here? Oh, glob, it feels like a hot sauce-coated cheese greater rubbing against my eyes. No… it’s like a mace-painted micro-plane on my corneas.

Let’s walk through it. “Hits rivals like athletes hit balls,” I like. We won’t get into why, but I like it. And the “sweet spot” part is good too—it gets right to the meat of the story.

But do you see the problem?!

“Glyptodont dinosaurs”? “Glyptodont dinosaurs”?!

It makes me want to hit someone with a novelty hammer so large that it could actually seriously wound him or her.

I mean, I’d understand if they said something like “dimetrodon dinosaurs,” because, you know, they look a little dinosaury, even if they were synapsids, and lived in the Permian. And it might even be reasonable to say something like “pteranodon dinosaurs,” because they were reptiles too, after all, and at least they were around in the Mesozoic.

But glyptodonts? They were mammals! Argh! And they lived up into the Pleistocene… they were around at the same time as humans! Oh, Telegraph…

Anyway.

Glyptodonts were basically armadillos the size of small cars. They had massive, armored tails, and, apparently, scientists have figured that there was a particular spot on the tail where they would most likely try to center force when swinging the appendage to defend themselves. Like bat- and racquet-using athletes who try to hit balls with a certain area of the bat or racquet to balance power and stress on their wrists and arms, some glyptodont species grew a large spike right at this “sweet spot,” suggesting that it was a practical development, and not just generally for show.

What, though, do you suppose glyptodonts were hitting with that tail? They first evolved in South America, where the top predators were a group of massive flightless birds, nicknamed “Terror birds.” But as big and scary as the terror birds were, glyptodonts were substantially more massive, and the armor alone seems like overkill, let along the club tail. Also, there’s some debate as to whether the terror birds were even carnivorous.

But, then again, organisms don’t evolve traits like that for nothing. So hopefully something was getting clubbed. Like dinosaurs.

PS—Check out the SMM’s dinos and fossils gallery for skeletons of both a glyptodont and a terror bird. See how very un-dinosaur they are.

Tyrannosaurus rex: Ready to gulp you down.
Tyrannosaurus rex: Ready to gulp you down.Courtesy Mark Ryan
Talk about fun. Take this cool quiz to see how long you'd have to be in a T-rex's digestive tract before you'd be totally digested. Evidently, it would take a guy my size about 17 hours. This is important information to have that could someday save your life. You never know when knowledge like this might come in handy. Take the quiz yourself.

The lead story of Sunday's Star-Trib travel section is about a travel opportunity in Wyoming where families can help dig for dinosaur bones. While time is dwindling down on this summer, it's a vacation destination to keep in mind for next year. BTW: I know the author of this story and warned her that too many trips like this might lead her kids to actually working for a museum!!!

Aug
10
2009

Typical T. rex?: Image modified slightly by JGordon.
Typical T. rex?: Image modified slightly by JGordon.Courtesy ArthurWeasley
Oh, paleontologists… with your grabby little claws… always grabbing for the juiciest headlines… late to the table of the hard sciences, where your neighbors long ago grew fat and respected.

JK, of course. You’re a spunky young science, paleontology, and I love you for it. And who doesn’t want headlines? Why do you think I keep lighting fireworks off on my roof? If you’ve got something as loved, feared, and debated as the mighty Tyrannosaurus rex as your specialty, why not be a little provocative?

And so it went with a couple of paleontologists based out of Beijing and Munich. They’re all, “Ahem. Ahem. Is this thing on? Hello? We think, ah, that the Tyrannosaurus rex probably ate a lot of baby dinosaurs, and not so many fearsome adult dinosaurs. And, um, we…”

And then the press is all, “Say what?! Are you trying to say that the T. rex was just a big, dumb baby-eater? You are?”

Scientists: “Sort of, but not exactly.”

Press: “Print it!”

And so we have a new contender in the “Fearsome Hunter vs. Giant Scavenger” ring: Fearsome Baby-Hunter!

The idea, say the scientists, is that it’d be a lot easier to go around eating weak little babies than to go around fighting big triceratops and stuff, so that’s probably what T. rex did. (T. rex and other large, two-legged meat eaters.)

That part makes sense. Even if you’re as big and strong as the T. rex certainly was, eating something that can’t hurt you or run away from you pays off a lot more than eating something that can hurt seriously damage you, and takes a lot of energy to get. If you were a dinosaur, babies would probably be your favorite food. They’d be like the equivalent of individual serving yogurts. (Fun, delicious, and easy to eat.) That doesn’t mean that there were no epic dino-battles… they would have just been rare, I guess.

The paleontologists go on to say that T. rex-like dinosaurs specialized in baby eating so much, that it could explain the lack of immature dinosaurs in the fossil record. Juveniles would have been eaten whole, or at least in large chunks, their predators digesting the bones and everything. This would also explain, the claim, the low occurrence of bite marks on fossilized adult dinosaur bones—they just weren’t getting bitten much, if they made it to adulthood.

That’s where some of the theory falls apart for me. Why would an organism expend so much energy growing and maintaining a body the size of T. rex’s if its main prey was small and weak? Also, did dinosaurs just leave their young lying around for any old predator to eat? Unless a predator were small and sneaky (and whatever else T. rex was, it wasn’t small and sneaky), and could grab baby dinos on the sly, one would think that it would run into some protective parent dinosaurs pretty often. And then they’d have to fight, which defeats the purpose of going after little dinosaurs in the first place.

The lack of scarred adult bones seems to be incidental too. If a dinosaur died from whatever scarred its bones, I’d assume that it would be totally eaten (either by its killer, or later, by scavengers) before it fossilized. And maybe the type of wound that would leave scars on a bone would likely kill the attacked animal. And if the creature didn’t die, if it healed totally, it still might get eaten later on. And most animals don’t fossilize anyway.

And do we need a reason why there aren’t more baby dinosaur skeletons? They survive to adulthood, no baby skeletons. They get eaten, no skeleton. (Babies were bound to have been eaten, even without large dinosaurs specializing in eating them.) Even if they died of other causes, I wonder if their parents would eat the body themselves, or at least push it out of a nest, or leave it behind (where it would get eaten).

I wonder, too, if the ratio of baby dinosaurs to adults is similar in periods and areas without large theropods. (Theropods are the group of two-legged meat eaters T. rex belonged to.) If it’s the same, then the reason for so few specimens would have to be low fossilization rates, or a sampling problem, or just that everything was eating baby dinosaurs, not just theropods (which is a much less interesting claim to make).

Anyone care enough to offer an opinion?