Interspecies sexual behaviour between a male Japanese macaque and female sika deer
Résumé
Interspecies sexual behaviour or ‘reproductive
interference’ has been reported across a wide range of
animal taxa. However, most of these occurrences were
observed in phylogenetically close species and were
mainly discussed in terms of their effect on fitness,
hybridization and species survival. The few cases of
heterospecific mating in distant species occurred between
animals that were bred and maintained in captivity. Only
one scientific study has reported this phenomenon,
describing sexual harassment of king penguins by an
Antarctic fur seal. This is the first article to report mating
behaviour between a male Japanese macaque (Macaca
fuscata yakui) and female sika deer (Cervus nippon
yakushimae) on Yakushima Island, Japan. Although Japanese
macaques are known to ride deer, this individual
showed clearly sexual behaviour towards several female
deer, some of which tried to escape whilst others accepted
the mount. This male seems to belong to a group of
peripheral males. Although this phenomenon may be
explained as copulation learning, this is highly unlikely.
The most realistic hypothesis would be that of mate
deprivation, which states that males with limited access to
females are more likely to display this behaviour. Whatever
the cause for this event may be, the observation of
highly unusual animal behaviour may be a key to understanding
the evolution of heterospecific mating behaviour
in the animal kingdom.