Species separation in artiodactyl communities by the criterion of territorialism: The hypothesis of olfactory exclusion

Abstract

The interspecies distinctions were determined in two artiodactyl communities from geographically distant populations by means of discriminant analysis of four traits: altitude, mean body mass, mean group size, and territorialism. These communities inhabit similar landscapes of the Altai and Himalayas. They are formed by species with different territorial systems (year-round and seasonal), and also by species without such systems. By this attribute, the species ratio was 1 : 1 : 2 in the community of Altai and 1 : 3 : 3 in the Himalayan community. Territorial system diversity is a natural character of the communities under study; it provides the basis for essential distinctions in the structure of specific biological signal fields. An inhibiting role of year-round territorialism in population separation was demonstrated. In it, species are characterized by a seasonal pattern of scent marking by dermal gland secretion. Based on the results, a principle was formulated for the separation of species with active biological signal fields in Cetartiodactyla communities. According to this principle, two species with year-round territorialism, the basic element of which is intensive scent marking, cannot occupy the same habitat. The mechanism of olfactory exclusion of mammalian species with specific functioning of the olfactory system is discussed.