BODY SIZE-RELATED COEXISTENCE - AN APPROACH THROUGH ALLOMETRIC CONSTRAINTS OM HOME-RANGE USE

This paper investigates whether body size-related constraints on home- range resource harvesting could lead to coexistence between interspeci fic competitors of different body size under conditions of complete ni che overlap. With this objective, I analyzed the influence of body siz e on induced and sustainable resource limitation and its implications on the interaction between an individual and a fixed biomass of larger competitors in a four-dimensional space, consisting of two spatial di mensions describing competitor home range, resource availability, and time. It was shown that body size-related spatiotemporal constraints o n home-range resource harvesting, trophic optimization, and relativity of resource availability determine absolute and relative amounts of u nused home-range resources, restricting the influence of resource limi tation induced by an individual to a definite size distance around its size. It was therefore concluded that: (1) when competition occurs as ymmetrically with a superiority of large animals, size differences alo ne could allow coexistence, independently of any kind of resource part itioning; and (2) superiority of large animals should result from the resource density control that a larger competitor imposes on the small er one whenever size differences for stable coexistence occur. Existin g evidence of an inefficiency in home-range resource exploitation seem s large enough to suggest a view of guilds based on a hierarchy of inc lusive home ranges.