Aquatic flatworms use chemical cues from injured conspecifics to assess predation risk and to associate risk with novel cues

Wisenden, BD Millard, MC

Bd. Wisenden et Mc. Millard, Aquatic flatworms use chemical cues from injured conspecifics to assess predation risk and to associate risk with novel cues, ANIM BEHAV, 62, 2001, pp. 761-766

40

INGLESE

Article

Animal Sciences","Neurosciences & Behavoir

ANIMAL BEHAVIOUR

0003-3472 → ACNP

62

2001

4

761 - 766

ISI

0003-3472(200110)62:<761:AFUCCF>2.0.ZU;2-U

A growing number of aquatic organisms have been shown to display antipredat or behaviour in response to injury-released chemical cues from conspecifics . Here, we demonstrate a clear antipredator response in the form of avoidan ce behaviour by a free-living flatworm Dugesia dorotocephala to chemical cu es from injured conspecifics. This is the first demonstration of a chemical alarm cue in a platyhelminth. In a second experiment, we exposed planaria to combined cues of sunfish odour and planaria alarm cue, or sunfish odour alone. Planaria avoided the sunfish+alarm cue but did not avoid the sunfish odour, indicating no prior aversion to sunfish odour. When these same plan aria were subsequently retested 2 days later with sunfish odour only, plana ria that had previously received sunfish odour+alarm cue avoided the cue bu t planaria that had previously received sunfish odour alone did not. These data indicate that planaria learned to recognize sunfish odour as an indica tor of danger based on a single simultaneous exposure to conspecific alarm cue and the novel cue. This is the first demonstration of this phenomenon i n a platyhelminth and the simplest nervous system known to be capable of le arned risk association. (C) 2001 The Association for the Study of Animal Be haviour.