The record of fossil mammalian remains from Poggio Rosso, Upper Valdarno, represents one of the richest samples for deciphering paleobiological information on latest Pliocene land faunas of central Italy. The taphonomic imprinting of this bone accumulation formed by Pachycrocuta brevirostris is investigated to determine the time-averaging of the assemblage, the structure of the paleocommunity from which it originated, and the interactions among some of the species represented in it, as well as the paleobiology and paleoethology of the hyenas. The bones were accumulated in a short time (within a year) during an episode of severe drought. The harsh environmental conditions debilitated the fauna and exposed it to predators. Harsh conditions also forced clans of Pachycrocuta hyenas, which under normal circumstances would have been primarily scavengers, to turn into killers of prey that now were easier to subdue. Thus portions of killed prey were added to the scavenged carcass parts usually taken to the dens. Furthermore, the remains at Poggio Rosso seems to add weight to the hypothesis that middle latitude R brevirostris might have had seasonal breeding and parental care of cubs.