DOI: 10.5061/dryad.kd51c5bd3
title: Revisiting the burglar-alarm hypothesis: a behavioral cascade mediated by dinoflagellate bioluminescence

description: Bioluminescence is widespread among marine organisms and has evolved
 independently multiple times. While its specific adaptive value is
 diverse, bioluminescence in most cases mediates fundamental interactions
 between individuals (predator, prey, mates) and thus impacts ecosystem
 processes. One hypothesized value of bioluminescence in dinoflagellates is
 through the ‘burglar alarm’: grazers of phytoplankton will make the
 ambient water ‘glow’ as they swim, thereby attracting visual predators of
 the grazer, thus indirectly protecting the dinoflagellates. However, the
 most important grazers of dinoflagellates, copepods, are generally too
 small to elicit dinoflagellates to glow. Only individual cells captured by
 a copepod will flash, which in turn elicits a powerful escape response in
 the copepod. Here, we test a variant of this hypothesis that may work for
 copepods. The behavioral response of the grazer to the flashing of a
 captured dinoflagellate, rather than the flashing itself, attracts the
 attention of the grazer’s flow-sensing predators. We demonstrate that
 bioluminescence in three dinoflagellates reduces the clearance- and
 ingestion rate of nauplii of the copepod Temora longicornis. The presence
 of bioluminescent cells also elicited an increased frequency of high-speed
 jumps of the grazers. The increased jump frequency elevated the
 detectability of the grazers to a flow-sensing predator, the copepod
 Centropages typicus, consequently leading to increased predation mortality
 of T. longicornis nauplii. The consequent behavioral cascade mediated by
 bioluminescence works for small grazers that cause only single cells to
 flash, unlike the traditional description of the burglar alarm.
description: # **Revisiting the burglar-alarm hypothesis: a behavioral cascade mediated
 by dinoflagellate bioluminescence**
 ## Description of the data
 and file structure The excel file contains five sheets, with the variables
 in each sheet as below: **1) Grazing exp.** * Cell concentrations of
 dinoflagellates (at flashing and nonflashing phases) at the beginning and
 end of grazing experiments in the presence and absence of *Temora* *
 Number of *Temora* in each replicate * Clearance- and ingestions rates of
 *Temora* on dinoflagellates at flashing and nonflashing phases **2) Jump
 behavior** * Jump-related parameters (including jump frequency, jump
 duration, jump velocity, jump time proportion and jump distance) in
 *Temora* responding to dinoflagellates at flashing and nonflashing phases
 under three cell concentrations **3) Predation exp.** * *Temora* number in
 control groups in predation experiments * Number and dry weight of
 *Temora* at the end of predation experiments * Number and dry weight of
 *Centropages* at the end of predation experiments * Clearance- and
 ingestions rates of *Centropages* on *Temora* in the presence of
 dinoflagellates at flashing and nonflashing phases **4) *Temora* size in
 grazing exp.** * Body length of *Temora* feeding on dinoflagellates at
 flashing and nonflashing phases in the grazing experiments **5) Both size
 in predation exp.** * Body length of *Temora* and prosome length of
 *Centropages* in the predation experiments All blank cells are explained
 in each sheet, separately. ## Sharing/Access information NA. ##
 Code/Software NA.