Slashdot Mirror
Pack-Hunting Dinosaurs Found As Large As T-Rex
1369IC writes "The Washington Post is reporting that the recently unearthed Mapusaurus roseae was as large as a T-Rex and may have hunted in packs. The fossils were found in Patagonia, in Argentina, though not enough were found to reconstruct an entire specimen. The meat-eaters probably lived in the same time and place as the 125-foot-long Argentinosaurus, the largest known dinosaur." From the article: "T. rex was equipped to attack and destroy animals its own size, Currie said, but Mapusaurs perhaps could 'go in, strike, pull and see what to do next,' a strategy that could work against larger animals, especially if the predators attacked together -- the prehistoric equivalent of a pack of wolves cornering a bison."
Yeah, blame capitalism. This wouldn't even have been discovered without it. I am sure this is the first time, ever, something was named after a person. Ever.
Was the T. rex a vicious predator or a lumbering scavenger? You seem quite confident with your position, but at the same time you forget about the facts that point to the other direction.
Arms? I don't need no steenking arms to be a predator! If small arms == scavenger, most of the big theropod dinosaurs would have been scavengers. Not likely. Sight? The brain of T. rex seems to indicate it had an excellent sense of sight. Smell and sense of balance, too. Feet? Yeah, T. rex probably wasn't a sprinter. But it was very heavily built, which could mean a position as a top predator that took on the biggest, slowest and heaviest herbivores. As you already mentioned yourself, it may not have needed to be quick. It's neck is as strong as anything found in dinosaurs, but apparently at the same time it was able to make very fast and coordinated movements. Predators can also get big to be able to hunt big prey, and dinosaur prey-predator ecology was very likely to be different from its mammalian equivalent. Yes, T. rex was around right up until the KT extinction, but it wasn't there since the dawn of dinosaurs. It was actually one of the last dinosaur species known to have evolved, along with the likes of Triceratops and other late Cretaceous dinosaurs.
So, make of these facts what you will. The only true fact, though, is that T. rex could have been an active predator or a scavenger. We simply don't and cannot know for sure. My take is it was probably both. A carnivore that big should have eaten tonnes of dead meat regularly to stay alive, and I find it unlikely that dead dinosaurs big enough to satisfy a T. rex's hunger were lying around in that large numbers. Just like lions today, it would be happy with a carcass in case such was easily available. As for pack hunting, that's mostly pure speculation.
Oh, and the carnivorous fossil elephants of tomorrow. As it was already pointed out in another reply, the future paleontologists would look at the molars of the elephants and make the right conclusion that the animal was a herbivore. Size doesn't make animals carnivores, neither elephants nor dinosaurs.