To add to a calendar week ofcreature discoverythat equate to thestuff of nightmares , meet the innocent - looking sea urchin with the most surprising ( and terrific ) justificative weapon . When under attack , it liberate century of still - biting “ heads ” with “ jaws ” that attach to their attacker , delivering tiny venomous bites .
This “ waterborne pursuit - deterrent signaling ” , as the researchers describe it , was discovered by marine life scientist Hannah Sheppard - Brennand and her team from Southern Cross University , Australia . It ’s not strange for brute to have projectile defenses , however the discovery thatTripneustes gratillareleases sting head that seem to be subject of independent activeness is definitely unique .
“ The globiferous pedicellariae [ head ] are minute and terrifying , ” Sheppard - Brennand admit toNew Scientist . “ When they were first observed , they were guess to be parasites , as they give the appearance of independent action from the primary animal . ”
Pedicellariae heads are commonly found in echinoderms . The little pincer - like head are attach to a transferrable stalk and are used for attracting food as well as fending off predators . They usually continue attached to the urchin , though . write inThe American Naturalist , the young study describe howT. gratilla’spedicellaria heads in reality detach from the trunk in a defensive cloud , seek out the assaulter , latch on , and carry on biting , releasing their venom .
The researchers tested this in both field and lab conditions and found the same result . They simulate fish attacks in the research laboratory by lightly poking the urchin and they commonly responded by bring out ten of the little biters . Sheppard - Brennandexplainedthat it takes between 40 and 50 days for the pedicellariae to rectify , but because they have so many of them , they only need to release a small amount . However , they witnessed an individual producing hundreds in just 30 seconds , too .
The research worker reason that this unusual defense chemical mechanism could help excuse how ocean urchin can reach such high denseness on reefs . Basically , they terrify the bejeezus out of anything that dares approaching .
