Yuan Huang, Fredrik Ryderheim, Thomas Kiørboe
This is a plain language summary of a Functional Ecology forum article which can be found here.
The biological production of bioluminescence is a widespread phenomenon in the oceans, and its hypothesized adaptive significance is diverse. Dinoflagellates, the single-celled aquatic protists, are capable of producing bioluminescence, which is responsible for the observed “glowing” or “burning” seas at night. The burglar alarm hypothesis is a popular explanation of the adaptive value of bioluminescence in dinoflagellates: when dinoflagellates flash due to the disturbance generated by a swimming grazer, making the grazer ‘glow’, it may attract the grazer’s visual predators, thereby benefiting the dinoflagellate population.
Here we explore a variant of the burglar alarm hypothesis that may work for copepods, the primary grazers of dinoflagellates: The behavioral response of a copepod grazer to the flashing of a captured dinoflagellate, rather than the flashing itself, attracts the attention of the grazer’s (blind) predators. We showed that the flash of a single captured cell elicits a powerful escape response in the copepod; this generates a fluid disturbance that attracts the attention of the copepod’s flow sensing predators. This behavioral cascade mediated by bioluminescence works for small grazers that cause only single cells to flash, unlike the traditional description of the burglar alarm.
Functional Ecology: Plain Language Summaries 