Ancient 8-foot sea scorpions not as frightening as previously thought
By ANIMonday, January 3, 2011
WASHINGTON - Huge ancient sea scorpions, believed to be terrors of the seas 470 million to 370 million years ago, long before the dinosaurs appeared, might actually have been timid scavengers or even vegetarians, according to U.S. researchers.
Sea scorpions, known as pterygotid eurypterids, were arthropods, a group that included insects and crabs. Though not actually scorpions, many of the animals had tails ending in spikes, which got them their name.
These 8-foot-long monstrous bug-like creatures had large claws laden with sharp spines.
But researchers said these claws possessed very little crushing power.
They analyzed claws from a group of one of the largest sea scorpions, Acutiramus, which lived about 416 million to 419 million years ago and calculated that the pincers could only safely apply no more than 5 newtons of force without damaging themselves.
This would make them incapable of penetrating into even a medium-size horseshoe crab’s armor, which needs 8 to 17 newtons to crack open.
“We have a group that in many cases was perceived as big, bad animals, sort of theTyrannosaurus rex of the seas of their time,” Fox News quoted researcher Richard Laub, a paleontologist at the Buffalo Museum of Science in New York, as telling LiveScience.
“Frankly, that was my view when we began our work,” he said.
“Our results derail the image of these imposing-looking animals, the largest arthropods yet known to have existed, as fearsome predators,” said Laub.
“It opens the possibility that they were scavengers or even vegetarians,” he added.
The researchers also found that Acutiramus did not have elbow joints between the claws and the body, making it easier for them at capturing prey on the seafloor than at hunting swimming creatures.
They suggested that sea scorpion pincers could have been used to entrap and slice soft-bodied and relatively weak prey.
The arrangement of the spines and the serrations on the claws suggested that they might have been used in tandem - one would grasp food, and the other would pull them along the serrations, tearing and shredding that way, like tearing a piece of paper, said Laub.
The findings are published in the December 20 bulletin of the Buffalo Society of Natural Sciences. (ANI)
