Alpheus is the most diverse shrimp genus. Some of their defining characteristics are orbital hoods and an oversized claw which they use for defense and killing prey. When this claw is snapped shut it shoots out water which creates a low pressure air bubble behind it. The bubble reaches temperatures of 5000 degrees Kelvin (half of the heat of the sun)(4). When the bubble pops it makes a loud sound and produces a flash of light. The shockwave from the pop stuns or kills the shrimp’s prey. The shrimp have developed orbital hoods to protect their eyes from the shockwave. However, this orbital hood leads to poor vision. In order to make up for this shortcoming some shrimp have developed a symbiotic relationship with gobies. The gobies protect the shrimp from predators by looking around for predators. When a goby detects a predator it moves its tail in a way that warns the shrimp. The shrimp feels the movements with its antennae and they both go hide. The shrimp and goby live in close proximity.
- (1) Smithsonian Tropical Research Institute, Alpheid Shrimp Database,http://biogeodb.stri.si.edu/bioinformatics/alpheus/GenusAlpheus.html. November 19, 2010.
- (2) ESA, The Sharp Shooter of Marine Life,http://www.esa.org/esablog/tag/pistol-shrimp/. November 19, 2010.
- (3) Chris Brumbaugh, The Pistol Shrimp,http://users.soe.ucsc.edu/~cbrumbau/BME200/. November 19, 2010.
- (4) How Snapping Shrimp Snap (and Flash),http://stilton.tnw.utwente.nl/shrimp/. November 19, 2010.
I like where this brief summary is going (it is fascinating!) but it starts off as if it is just for the genus -- but it is associated with the family so should cover more. Might be good to link the article to the appropriate goby page to help readers get more information.