Nav: Home

Sea scorpions: The original sea monster

April 18, 2017

Four hundred and thirty million years ago, long before the evolution of barracudas or sharks, a different kind of predator stalked the primordial seas. The original sea monsters were eurypterids--better known as sea scorpions.

Related to both modern scorpions and horseshow crabs, sea scorpions had thin, flexible bodies. Some species also had pinching claws and could grow up to three metres in length. New research by University of Alberta scientists Scott Persons and John Acorn hypothesise that the sea scorpions had another weapon at their disposal: a serrated, slashing tail spine.

Armed and dangerous

"Our study suggests that sea scorpions used their tails, weaponized by their serrated spiny tips, to dispatch their prey," says Scott Persons, paleontologist and lead author on the study.

Sparked by the discovery of a new fossil specimen of the eurypterid Slimonia acuminata, Persons and Acorn make the biomechanical case that these sea scorpions attacked and killed their prey with sidelong strikes of their serrated tail.

The fossil, collected from the Patrick Burn Formation near Lesmahagow, Scotland, shows a eurypterid Slimonia acuminate, with a serrated-spine-tipped tail curved strongly to one side.

Powerful weapons

Unlike lobsters and shrimps, which can flip their broad tails up and down to help them swim, eurypterid tails were vertically inflexible but horizontally highly mobile.

"This means that these sea scorpions could slash their tails from side to side, meeting little hydraulic resistance and without propelling themselves away from an intended target," explains Persons. "Perhaps clutching their prey with their sharp front limbs eurypterids could kill pretty using a horizontal slashing motion."

Among the likely prey of Slimonia acuminata and other eurypterids were ancient early vertebrates.
-end-
The paper, "A sea scorpion's strike: New evidence of extreme lateral flexibility in the opisthoma of eurypterids," was published in The American Naturalist in April 2017.

University of Alberta

Related Fossil Articles:

Fossil fish gives new insights into the evolution
An international research team led by Giuseppe Marramà from the Institute of Paleontology of the University of Vienna discovered a new and well-preserved fossil stingray with an exceptional anatomy, which greatly differs from living species.
What color were fossil animals?
Dr. Michael Pittman of the Vertebrate Palaeontology Laboratory, Department of Earth Sciences, The University of Hong Kong led an international study with his PhD student Mr.
New Cretaceous fossil sheds light on avian reproduction
A team of scientists led by Alida Bailleul and Jingmai O'Connor from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences reported the first fossil bird ever found with an egg preserved inside its body.
Fossil deposit is much richer than expected
Near the Dutch town of Winterswijk is an Eldorado for fossil lovers.
Researchers add surprising finds to the fossil record
A newly discovered fossil suggests that large, flowering trees grew in North America by the Turonian age, showing that these large trees were part of the forest canopies there nearly 15 million years earlier than previously thought.
More Fossil News and Fossil Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...