Animal behaviour and plundered mammals: Is the study of mating systems a scientific luxury or a conservation necessity?

Darwin claimed ''the practice of polygamy leads to the same results as would follow from an actual inequality in the number of the sexes'' Biologists interested in conservation have focused on offshoots of this deceptively simple theme including reproductive competition, sexual selection, and copulatory dynamics. Few would dispute that an understanding of mating relationships is important. Here, I ask - important for what? Using two species of large mammals that have suffered 97% reductions in population size, I make two points. First, in attempts to restore populations some individuals or even lineages may be competitively inferior, leaving behind few or no progeny, a scenario depicted empirically using two lineages of North American bison (Bison bison). Second, where human utilization of economically valuable morphological structures has been proposed (as for rhino horns), knowledge of current utility is required to predict possible biological effects. Preliminary data on black rhinos (Diceros bicornis) suggest that dehorned mothers are less able to defend their calves from spotted hyenas (Crocuta crocuta) than intact mothers. For conservation, some issues in animal behaviour will always hold greater relevance than others. The study of mating systems, unless defined very broadly, is likely to have more relevance in captive propagation and population restoration than other issues involving the conservation of biodiversity.