Ancient Scorpion Was Bigger Than Car

Braddy's partner paleontologist Markus Poschmann found the claw fossil several years ago in a quarry near Prum, Germany, that probably had once been an ancient estuary or swamp.

"I was loosening pieces of rock with a hammer and chisel when I suddenly realized there was a dark patch of organic matter on a freshly removed slab. After some cleaning I could identify this as a small part of a large claw," said Poschmann, another author of the study.

"Although I did not know if it was more complete or not, I decided to try and get it out. The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilize it," he said.

Eurypterids, or ancient sea scorpions, are believed to be the extinct aquatic ancestors of today's scorpions and possibly all arachnids, a class of joint-legged, invertebrate animals, including spiders, scorpions, mites and ticks.

Braddy said the fossil was from a Jaekelopterus Rhenaniae, a kind of scorpion that lived only in Germany for about 10 million years, about 400 million years ago.

He said some geologists believe that gigantic sea scorpions evolved due to higher levels of oxygen in the atmosphere in the past. Others suspect they evolved in an "arms race" alongside their likely prey, fish that had armor on their outer bodies.

Braddy said the sea scorpions also were cannibals that fought and ate one other, so it helped to be as big as they could be.

"The competition between this scorpion and its prey was probably like a nuclear standoff, an effort to have the biggest weapon," he said. "Hundreds of millions of years ago, these sea scorpions had the upper hand over vertebrates -- backboned animals like ourselves."

That competition ended long ago.

But the next time you swat a fly, or squish a spider at home, Braddy said, try to "think about the insects that lived long ago. You wouldn't want to swat one of those."