Recent wins and losses can inform individuals about their relative fighting abilities and modify their subsequent contest decisions. Using a mangrove rivulus, Kryptolebias marmoratus, we tested the hypothesis that visual and limited physical interactions can also convey information and modify subsequent contest decisions. Individuals were exposed to a stronger or weaker conspecific through a glass or a mesh partition before a contest with a size-matched naïve opponent. Individuals were expected to (a) assess themselves to have worse/better fighting ability and behave less/more aggressively after having interacted with a stronger/weaker conspecific and (b) display different degrees of behavioural modifications for the two partition treatments (mesh-partition > glass-partition). The results showed that interactions with a stronger/weaker conspecific through a glass partition did not have a strong effect on the fish's subsequent contest behaviour. Restricted physical interaction with a stronger/weaker conspecific through a mesh partition, however, had an unexpected effect, causing individuals to behave more/less aggressively (matching the behaviour of the conspecifics) and/or win more/fewer subsequent contests. These results indicate that contest resolution is important for the fish to exhibit the loser–winner effects (i.e. behaving less/more aggressively after having lost/won against a stronger/weaker conspecific) detected in previous studies of the fish. We propose and discuss the possibility that the “behavioural matching” of the mesh-partition treatment results from unresolved physical interactions with a stronger/weaker conspecific causing the individuals to either anticipate stronger/weaker opponents in subsequent competitions or assess themselves to be an equally good/bad fighter as the conspecific. The results of previous studies and the present study of the fish show that pre-exposing an individual to the same type of conspecifics could elicit diverse, sometimes opposite, behavioural responses depending on how the individual is permitted to interact with the conspecific.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology