Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Extinct sea scorpion gets a Yale eye exam, with surprising results

11.07.2014

Poor peepers are a problem, even if you are a big, bad sea scorpion.

One minute, you're an imperious predator, scouring the shallow waters for any prey in sight. The next, thanks to a post-extinction eye exam by Yale University scientists, you're reduced to trolling for weaker, soft-bodied animals you stumble upon at night.


Sam Ciurca, a curatorial affiliate with the Department of Invertebrate Paleontology at Yale University, holds a model of a pterygotid.

Credit: Yale University

Such is the lot of the giant pterygotid eurypterid, the largest arthropod that ever lived. A new paper by Yale paleontologists, published in the journal Biology Letters, dramatically re-interprets the creature's habits, capabilities, and ecological role. The paper is titled "What big eyes you have: The ecological role of giant pterygotid eurypterids."

"We thought it was this large, swimming predator that dominated Paleozoic seas," said Ross Anderson, a Yale graduate student and lead author of the paper. "But one thing it would need is to be able to find the prey, to see it."

Pterygotids, which could grow more than two meters long, roamed shallow, shoreline basins for 35 million years. Because of the creatures' size, the long-toothed grasping claws in front of their mouth, and their forward-facing, compound eyes, scientists have long believed these sea scorpions to be fearsome predators.

But research by Richard Laub of the Buffalo Museum of Science cast doubt on the ability of pterygotids' claws to penetrate armored prey. Yale's eye study further confirms the idea that pterygotids were not top predators.

"Our analysis shows that they could not see as well as other eurypterids and may have lived in dark or cloudy water. If their claws could not penetrate the armor of contemporary fish, the shells of cephalopods, or possibly even the cuticle of other eurypterids, they may have preyed on soft-bodied, slower-moving prey," said Derek Briggs, the G. Evelyn Hutchinson Professor of Geology & Geophysics at Yale and curator of invertebrate paleontology at the Yale Peabody Museum of Natural History. Briggs co-authored the paper.

Victoria McCoy, a Yale graduate student, developed an innovative mathematical analysis method to understand the properties of the sea scorpions' eyes. Yale also used imaging technology with backscattered electrons on a scanning electron microscope to reveal the eye lenses without damaging the fossils. The team compared the results with the eyes of other extinct species during the same period, as well as modern-day species such as the horseshoe crab.

Although the data couldn't be used to determine nearsightedness or farsightedness, it revealed a basic visual acuity level for the sea scorpions, which had thousands of eye lenses. "We measured the angle between the lenses of the eye itself," Anderson said. "The smaller the angle, the better the eyesight."

Unfortunately for pterygotids, their eyesight proved less than exceptional, note the researchers. In fact, their vision worsened as they grew larger. It certainly wasn't on par with high-level arthropod predators such as mantis shrimp and dragonflies, said the scientists.

"Maybe this thing was not a big predator, after all," Anderson said. "It's possible it was more of a scavenger that hunted at night. It forces us to think about these ecosystems in a very different way."

The Yale team's vision testing methodology may prove instrumental in understanding how other species functioned, as well. "You could use it on a number of different organisms," according to Anderson. "It will be particularly useful with other arthropod eyesight examinations."

Former Yale postdoctoral fellow Maria McNamara of University College Cork also co-authored the paper. The research began as a project in a fossil preservation class Briggs taught at Yale.

Jim Shelton | Eurek Alert!
Further information:
http://www.yale.edu

Further reports about: Peabody creatures ecological lenses penetrate scorpions

More articles from Life Sciences:

nachricht Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology

nachricht Migrating Cells: Folds in the cell membrane supply material for necessary blebs
23.11.2017 | Westfälische Wilhelms-Universität Münster

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>