Ankylosaurs Had Composite Armor

An anonymous reader writes "Ankylosaurs were the most heavily armored dinosaurs. Researchers thought their protective plates were a lot like modern crocodiles. But a new study by a University of Bonn grad student Torsten Scheyer found that fibers in the plates were woven for strength and lightness much like Kevlar or fiberglass. Good thing, as ankylosaurs had to contend with T. rex."

Comments

how do they know what it was made of?

[jstave]

I understand how they can talk about the structure of the armor, but, given that these are fossils, and therefore have had their organic substance replaced by minerals, how do they know what the structure was composed of?

Re:how do they know what it was made of?

[Mattcelt]

Imagine a fish who dies and is fossilized. The scales show up as patterns in the fossil, right? In fact, depending on how it's preserved, sometimes you can cut through them and see a fairly accurate cross-section of the scales.

Now imagine a woven rush basket that somehow becomes fossilized (not likely, but just go with it). Now looking at the fossil, you're going to see the rises and falls of the individual reeds as they transverse all the perpendicular reeds in the design, and you'll be able to see the remnants of the grain running across and down the design as well. That's the sort of thing the student was studying - the anklyosaurus had a similar structure, only on a much smaller scale.

Fossilization doesn't turn something into a piece of amorphous rock - it preserves the topography (at least) of what was fossilized. So it's possible to examine not only the major features (skeletal structure, etc.) but also minor ones which were preserved. Some fossils, if preserved before flesh decay occurred (frozen instantly, caught in a tar pit, etc.) can even have the features of skin imprinted on the rock. That's how we know archeopteryx had feathers, for instance.

Hope that helps!

Nitpick

[SimianOverlord]

had to contend with T Rex

Not so. The Tyrannosaurus Rex was, according to consensus of scientific opinion, a opportunistic scavenger rather than an out and out predator, despite what films such as Jurassic Park portray. Heavy plate armour is so successful a defense mechanism, you might wonder why many more species don't utilise it.

This just goes to show that Nature, with a decent head start, can produce some pretty spectacular materials, an example that springs to mind is Morpho menelaus a butterfly with striking laser-blue irridescent wings, which uses an optical trick to make them shine so brightly. I was always fascinated by a little tray my father had when I was a kid, which was just the top side of the wings of these butterflies pressed under glass. I had a hard time believing it was from an organic being. Anyway, you can't get things like that anymore (I've looked) which is probably due to them having to be a protected species. Shame on all of us really, for hunting these creatures to near extinction, like the dinosaurs.

Re:Nitpick

[centauri]

Shame on all of us really, for hunting these creatures to near extinction, like the dinosaurs.

Hey, man, it was them or us. After you lose half your family to an iguanadon or an iridescent butterfly, you'll quickly ditch your sentimental way of thinking.

Re:Nitpick

[mcmonkey]

A creature doesn't get to be a 10 ton monster by being an "opportunistic scavenger".

It worked for Bill Gates.

Hay-ooo!

Consensus?

[SmallFurryCreature]

All depends who you pick for your consensus.

I will ask you to label two modern creatures to show why talking about t-rex eating behaviour is so futile.

Would you label the Hyena as a predator or a scavenger? And the lion?

Modern studies show that the scavenger Hyena kills a higher percentage of its food then the lion. Yet many still label the killer hyena as the scavenger and the lion known to eat hyena left overs as the predator.

Some people claim that t-rex build was unsuitable to hunt (head to big unable to run for long). Some claim that it build was exactly right to an ambush style hunt where it would deliver one large trauma wound and then use its nose to track the animal as it slowly died.

The same nose could also be used to find already dead prey.

Most like t-rex filled both roles shifting from one to the other as circumstances dictated. There are pure predators who refure to eat already dead animals but they are rare. Most predators are also scavengers and even some well known herbivores eat meat if they come upon it.

Talking about the movie. If you want to nitpick then nitpick that movie itself describes that the T-rex has a good nose but is somehow unable to small a scared human right infront of it. Even my cat spots a meal if you rub its nose in it. And this animal mews when I open a paint can.

Re: Ankylosaurus?

[Black Parrot]

> Better call it Puteosaurus then.

ped- is the root you're looking for, though the site you linked thinks pedere means the same thing as pedare.

Modern materials

[mdielmann]

It's worth noting that your teeth get their strength from the same technique. Short story, your teeth are made from the same material as bone, but it's woven, leaving them stronger than bones.

kevlar and fiberglass?

[wibs]

Kevlar is pretty much useless against a knife attack - it's designed to collapse in front of an object with at least a little bit of distributed pressure (like a bullet), whereas a blade can slice right through it. By that logic, Kevlar-like armor to protect against a dinosaur's teeth would be just about as effective as a firm pillow. Meanwhile, fiberglass is damn near impossible to stab a knife through, while its effectiveness against bullets varies greatly depending on how it's made. In other words, pretty much exactly the opposite of Kevlar.

So I guess I must be missing something here... how is this dinosaur's armor similar to both Kevlar and fiberglass? Or is it really nothing at all like either of them except that it's strong and light?