Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Muscle powers spearing mantis shrimp attacks

22.11.2012
Spearing mantis shrimp attacks powered by muscle instead of ballistics

A hungry mantis shrimp may be the last thing that a passing fish sees before it is snatched from the water by the predator. Maya deVries from the University of California, Berkeley, says 'Spearer mantis shrimps stay in their sandy burrows and they wait for a fast-moving prey item to come by, but then they come out of nowhere and grab the prey with their long skinny appendages.'

However, little was know about how these vicious predators unleash their lightning-fast attacks. According to deVries, the spearing shrimp are closely related to smasher mantis shrimps, which pulverise the shells of crustaceans and molluscs with a single explosive blow from their mighty claws. Having decided to find out how the crustaceans unleash their deadly assaults, deVries says, 'We thought that the spearers would be just as fast – if not faster – than the smashers because they have a smaller time window in which to capture their prey.' deVries and her colleagues publish their discovery that Lysiosquillina maculata spearer mantis shrimps power their mighty spears with muscle alone while smaller Alachosquilla vicina spearer mantis shrimps use a more conventional catapult mechanism in The Journal of Experimental Biology at http://jeb.biologists.org.

Working with her PhD advisor, Sheila Patek, deVries took a short trip along the corridor to Roy Caldwell's lab to film some of his L. maculata mantis shrimps. Coaxing the nocturnal lobster-sized crustaceans to assault frozen prawns, deVries recalls that the animals were reluctant to attack; 'They probably didn't like the bright lights', she says. However, when the duo analysed the speed of the strikes, they were surprised that the spearer's harpoon speed was much slower than that of their smashing cousin's. Explaining that smashers can unleash strikes at speeds ranging from 10 to 23m/s, the duo were taken aback that L. maculata could only muster 2 m/s.

Smasher mantis shrimp store catapult energy in skeletal springs that they unleash during a deadly assault; therefore deVries analysed the trajectories of several L. maculata claws in action, and realised that the hefty crustaceans were not using the same mechanism. 'The spear has all the same components [as the smashers]', explains deVries, but she adds that the shape of some of the structures are subtly different and the spring did not deform to store energy prior to an attack – possibly because it is too stiff – preventing L. maculata from firing a ballistic attack. 'If the L. maculata movement is similar to other ambush predators that have muscle-driven strikes, it is possible that these guys are creating strikes with muscle movement', says deVries.

Next, deVries and Patek tested the reactions of another, smaller mantis shrimp, Alachosquilla vicina, to find out whether all spearing mantis shrimps have opted for muscle-powered strikes. Elizabeth Murphy filmed the animals snapping up brine shrimp however, it was obvious that the diminutive crustaceans were using a spring-loaded catapult to spear their nimble prey. The team could clearly see energy-storing deformations in the spring structure before the mantis shrimp unfurled their deadly assaults at 6m/s.

But the team were still puzzled by L. maculata's sluggish performance. Maybe the lab-based animals had become too unfit to produce explosive attacks? Traveling to Australia to film L. maculata hunting in the wild, the team were relieved to see that the animals' reactions were well within the range of speeds that they had measured in the lab. Adult L. maculata use muscle-powered attacks all the time.

Having confirmed that it is possible for the large shrimp to produce lightening-fast strikes without using a spring mechanism, deVries says 'We're trying to get more L. maculata in the lab to look at the complete size range in one species to see how the strike scales and to find out if there is a size threshold above which you can't have a spring-loaded strike anymore.'

IF REPORTING ON THIS STORY, PLEASE MENTION THE JOURNAL OF EXPERIMENTAL BIOLOGY AS THE SOURCE AND, IF REPORTING ONLINE, PLEASE CARRY A LINK TO: http://jeb.biologists.org/content/215/24/4374.abstract

REFERENCE: deVries, M. S., Murphy, E. A. K. and Patek, S. N. (2012). Strike mechanics of an ambush predator: the spearing mantis shrimp. J. Exp. Biol. 215, 4374-4384.

This article is posted on this site to give advance access to other authorised media who may wish to report on this story. Full attribution is required, and if reporting online a link to jeb.biologists.com is also required. The story posted here is COPYRIGHTED. Therefore advance permission is required before any and every reproduction of each article in full. PLEASE CONTACT permissions@biologists.com

Kathryn Knight | EurekAlert!
Further information:
http://www.biologists.com

More articles from Life Sciences:

nachricht World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes
17.07.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Plant mothers talk to their embryos via the hormone auxin
17.07.2018 | Institute of Science and Technology Austria

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Behavior-influencing policies are critical for mass market success of low carbon vehicles

17.07.2018 | Power and Electrical Engineering

Plant mothers talk to their embryos via the hormone auxin

17.07.2018 | Life Sciences

Subaru Telescope helps pinpoint origin of ultra-high energy neutrino

16.07.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>