Glowing dinoflagellate plankton bloom make some of themost beautiful sightsin nature . While feast their eyes on some of the extraordinary spectacles biologists have been mystify about why they do it . For the most studied of the many bioluminescent plankton species , the abbreviated flashes of light deter grazers that would otherwise eat them .
Animals such as fireflies utilise the electrical capacity to glow in the wickedness to draw partner , while others use it to attract their prey . Neither of these apply to the undivided - celled being that can turn night - time seas into shimmer fields of wild blue yonder . Yet there has to be some evolutionary advantage . Producing so much light requires a mint of get-up-and-go , and for organisms that ca n’t black market aside , it is risky to alert grazers to their presence .
Andrew Prevett of the University of Gothenburg studied the interactions ofLingulodinium polyedraand the copepods that feed on them using high - amphetamine , low - light - sensitive video . He reports inCurrent Biologythat whenL. polyedrasenses the presence of a copepod ( a form of humble crustacean ) it gives off a newsflash of blue - immature spark lasting around a one-tenth of a second . This induce the copepod crustacean to kibosh sweep the dinoflagellate towards its lip and countenance the target to escape while the copepod crustacean seek non - bioluminescent fair game .
L. polyedragrow at only a third of the rate of diatoms , another grade of plankton that populate the same waters , presumably because develop and put on bioluminescent capacities gets in the way of other things . In most portion this direct toL. polyedrabeing move by species capable of faster growth . Off the west coast of Sweden , however , the exception is copepod - deep waters . Presumably , the small crustacean keep rival plankton numbers down , offer quad for their sparkly first cousin .
" There are three democratic theories as to how bioluminescence protects dinoflagellate , " Prevett say in astatement . If the dinoflagellate produces toxins light source can be a way of alerting grazers this is something they do n’t want to eat . The sudden flash may also startle the grazer and disorientate it enough to tolerate the dinoflagellate to escape .
“ The third theory suggests that the flash acts as a form of burglar alarm , attracting the attention of a larger optic predator , like a fish , which could track and consume the copepod , ” Prevettadded . “ There is grounds to sustain each of these hypothesis and bioluminescence protection could be combination of some or all of the above . "
The benefit may vary by species and the grazers that feed on them . Not allL. polyedraare bioluminescent and Prevett ’s copepod were seen to feed happily on non - glowingL. polyedra , which fits poorly with the first account .
