RENEE MONTAGNE, host:
Back in the Paleozoic Era, things were pretty tough - violent storms, huge changes in oxygen levels, and not much dry land. In the water, there were giant carnivorous sea scorpions. Scientists already knew these creatures were big. Now they've found a fossil from the biggest sea scorpion yet.
Here's NPR's Jon Hamilton.
JON HAMILTON: Four hundred million years ago was a bad time to go swimming. There were lots of predators. And Erik Tetlie, a paleontologist at Yale, thinks sea scorpions were the scariest.
Dr. ERIK TETLIE (Paleontologist, Yale University): They kind of look like a flattened submarine. And then they had these massive claws in front, which could be up to a meter long, and then they have five pairs of legs and the last of these were the swimming legs, which were flattened paddles.
HAMILTON: Kind of like a lobster big enough to play in the NBA. Scientists called the sea scorpions eurypterids. Tetlie says even the fossils are intimidating.
Dr. TETLIE: My supervisor in Bristol used to say that he would rather be in a pool with a shark than in a pool with a eurypterid, and I think I would agree with that.
HAMILTON: Tetlie and his former boss are part of an international team reporting on a new fossil that's likely to enhance the sea scorpion's frightening reputation. The fossil came from a quarry in Germany. Its part of a claw and it's about 18 inches long. The creature it came from was probably eight-feet long - a record. Tetlie says giant sea scorpions apparently led a simple life.
Dr. TETLIE: They probably ate primitive fish, others smaller sea scorpions whatever they can get their claws into.
HAMILTON: Unlike modern scorpions, they didn't kill their prey with a poisoned stinger.
Dr. LORENZO PRENDINI (Assistant Curator, Invertebrate Zoology, American Museum of Natural History, New York): They would probably just sort of sink their fangs into it and start munching away.
HAMILTON: Lorenzo Prendini is a scorpion expert at the American Museum of Natural History in New York. He says eurypterids didn't need a stinger to subdue their prey.
Dr. PRENDINI: The spines on the claws would have inflicted a lot of damage. They have even ripped them apart with their claws. But I think a combination of that and the actual jaws, which are quite well-developed with fang-like structures, would have done the damage.
HAMILTON: Sea scorpions had their tender moments, too, like when thousands would gather in the shallow water to shed their outer skeletons and mate. About 255 million years ago, the sea scorpions disappeared. One factor may have been a decreased in the amount of oxygen in the oceans. But Prendini thinks they just got eaten when something even bigger and meaner evolved.
Dr. PRENDINI: They were certainly some enormous dinosaur relatives of the day, Ischisaurus and the like. I think they would have made short work of these guys.
HAMILTON: Prendini says survivors may have become smaller and ended up on land, though the fossil record isn't entirely clear on that.
Dr. PRENDINI: Modern scorpions are more closely related to other arachnids like spiders and mites and then a host of other peculiar creatures than they are to the sea scorpions. But all of them shared a common ancestor at some point in time.
HAMILTON: As for the giant sea scorpion, it's still a big deal in places like New York, where it is the official state fossil. The new finding is described in the current issue of the journal Biology Letters.
Jon Hamilton, NPR News.
NPR transcripts are created on a rush deadline by Verb8tm, Inc., an NPR contractor, and produced using a proprietary transcription process developed with NPR. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.