Three words: Monster sea bug
Three words: Monster sea bug This rendering provided by Yale University shows a Pentecopterus decorahensis. Earth’s first big predatory monster was a weird water bug, newly found fossils show. Almost half a billion years ago, Earth’s dominant large predator was a sea scorpion that grew to 5 feet 7 inches with a dozen claw arms sprouting from its head and a spike tail, according to a new study. (Patrick J. Lynch/Yale University via AP)
Three words: Monster sea bug
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Earth's first big predatory monster was a weird water bug as big as Tom Cruise, newly found fossils show.
Almost half a billion years ago, way before the dinosaurs roamed, Earth's dominant large predator was a sea scorpion. It grew to 5-foot-7. A dozen claw arms sprouted from its head and a spike tail, according to a study.
Scientists found signs of these monsters of the prehistoric deep in Iowa, of all places.
Geologists at the Iowa Geological Survey found 150 pieces of fossils about 60 feet under the Upper Iowa River. Part of the river had to be temporarily blocked to allow them to collect the specimens. Then scientists at Yale University determined they were a species from about 460 million years ago. Back then Iowa was under an ocean.
All of the action was in the sea then and it was pretty small scale, said James Lamsdell. He is a professor at Yale and the lead author of the study published in the journal BMC Evolutionary Biology.
"This is the first real big predator," Lamsdell said. "I wouldn't have wanted to be swimming with it. There's something about bugs. When they're a certain size, they shouldn't be allowed to get bigger."
The creature is named Pentecopterus decorahensis, after an ancient Greek warship. Lamsdell said it isn't technically a bug by science definitions. It's part of the eurypterid family. So it's basically a sea scorpion.
Those types of creatures "are really cool," said Joe Hannibal. He is the curator of invertebrate paleontology at the Cleveland Museum of Natural History. Hannibal wasn't part of the study. But he praised it for being well done, adding "this species is not particularly bizarre - for a eurypterid."
Unlike modern land scorpions, this creature's tail didn't sting. It was used more for balance and in swimming. But half this creature's length was tail, Lamsdell said.
There were larger sea scorpions half way around the world at the same time. But those were more bottom feeders instead of dominant predators, he said.
Lamsdell could tell by the way the many arms come out of the extended head how this creature grabbed prey. Then it pushed the food to its mouth.
"It was obviously a very aggressive animal," Lamsdell said. "It was a big angry bug."

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Why was the sea bug found in Iowa, which is hundreds of miles from the ocean?
Write your answers in the comments section below

  • whittaker,alyncia-cas
    9/10/2015 - 08:49 a.m.

    1. It was found in Iowa because Iowa was once under the ocean.

    2. As someone who isn't a fan of bugs, it's not very comforting to know that giant bugs used to roam the earth, even if they did live in the sea.

  • braidens-mci
    9/10/2015 - 11:31 a.m.

    they are cool and the are wired and they will be bad win the see peaple

  • ericy-1-mci
    9/10/2015 - 11:33 a.m.

    Way before dinosaurs, that is amazing. The bug is probably going to be a really scary and deadly.

  • stevenh-mci
    9/10/2015 - 11:47 a.m.

    It was found in Iowa because it's prey was in Iowa too.

  • cameronw-mci
    9/10/2015 - 11:53 a.m.

    cause the sea bug was in the ocean but over time the earth changed

  • pieros-wil
    9/10/2015 - 12:58 p.m.


  • cawaf-wil
    9/10/2015 - 12:58 p.m.

    Because Iowa was under the ocean when the creatures were alive

  • samanthas-1-ste
    9/10/2015 - 12:59 p.m.

    That bug is bigger than I am! The ocean holds some of the weirdest things.

  • gabriellar-wil
    9/10/2015 - 01:01 p.m.

    The sea bug was found in Iowa because 460 million years ago, Iowa was under an ocean. So, when Iowa finally became land, the fossils of the big predator was found under the lake.

  • alyssar-1-wil
    9/10/2015 - 01:01 p.m.

    because they were found in a river and iowa used to be under an ocean

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