Abstract: lsquoLekrsquo breeding systems, where males defend small, clustered mating territories, are thought to occur where the distribution of females is heavily clumped but males are unable to defend resources used by females. In this paper, we describe a breeding system in fallow deer where males are able to defend resources used by females but the most successful bucks instead defend small territories on a traditional mating ground; where the lek is sited in an area not heavily used by females at other times of year and is visited primarily by females in or close to oestrus; and where mating success on the lek is related to territory position and to male phenotype but not to the resources available on different lek territories. Comparisons with other ungulates suggest that lek breeding species fall into two groups: those where leks are regularly visited by herds of females many of which are not in oestrus and those, like fallow deer, where leks are visited primarily by oestrous females. In the latter species, it is unlikely that females visit the lek for ecological reasons.

Abstract: The relationships between 4-5 adult zebra stallions, living in a safari park, were investigated over a period of 5 years. Asymmetries in the distributions of a number of behaviours could be explained by adopting dominance as an intervening variable. Dominance in stallions was of a bipolar nature with on the one hand behaviours representing subordinance and defence, and on the other hand behaviours reinforcing and confirming dominance. Expression of formal dominance seems to play a minor role. The dyadic relationships of stallions differed as to the number of behaviours reflecting dominance relationships. Although often linear rank-orders could be constructed, these rank-orders were not necessarily identical. This means that the concept of dominance is of only limited value for describing relationships between zebra stallions.