Who Is Served First? Intraspecific Traits That Drive Arrival at Food Resource in Two <i>Phanaeus</i> (Coleoptera: Scarabaeinae) Species

ABSTRACT Intra‐ and interspecific interactions may structure complex competitive scenarios in which the arrival time at a resource may play a key role in determining how individuals and populations are maintained. The speed and efficiency by which the dung beetles locate and colonise dung pads, which comprise an ephemeral and randomly distributed resource, may vary according to their physiological condition, sex, and body temperature. This study aimed to analyse how the sex, morphological traits, physiological conditions, and body temperature of dung beetles determine the time each individual spends reaching food resources. We performed field observations in arenas, recording the time spent by Phanaeus pseudofurcosus Bathasar, 1939, and Phanaeus obliquans Bates, 1887 individuals to reach the food resource. Dung beetles with lower temperatures arrived more rapidly at the dung pad. The body temperature of female dung beetles was the only variable explaining arrival time at the dung pad, with warmer females of both species arriving later. Males of P. pseudofurcosus with more muscle mass arrived later at the dung pad than those with lower muscle mass. The body temperature of P. obliquans individuals arriving at the dung pad depended on the environmental temperature. In summary, the arrival of dung beetles at food resources is influenced by physiological condition and temperature, and is also a species and sex‐dependent dynamic. This pattern of arrival time appears to be determined by a complex set of species‐specific conditions, with each species responding to distinct physiological and thermal dynamics.