Abstract: Information on the present population and status of the Indian Wild Ass Equus hemionus khur Lesson, 1827, is scanty. For this reason I was prompted to undertake this brief fact-finding survey, especially as South African Horse Sickness had been reported in that part of India recently. The International Union for the Conservation of Nature and Natural Resources sponsored my expedition, and the World Wildlife Fund very kindly paid my travelling expenses from the eastern part of India to the furthest western tip of the country.

Abstract: Data are presented on the breeding behavior of two zebra species to test whether intra- and interspecific variation in male reproductive behavior and physiology are correlated with differences in female promiscuity. In one species, plains zebra (Equus burchelli) females live in closed membership single male groups and mate monandrously. In the other species, the Grevy's zebra (E. grevyi) females live in groups whose membership is much more temporary. Typically, associations with individual males are brief and mating is polyandrous. However, some females – those having just given birth – reside with one male for long periods, mating monandrously. These differences in female mating behavior generate variability in the potential for sperm competition. We show that behavioral differences in male investment in reproductive activities correlate with the potential for sperm competition. When mating with promiscuous mares, Grevy's zebra stallions made a greater investment in reproductive behavior (calling, mounting, ejaculations) than did stallions of either species when mating with monandrous females. The evolution of large testes size in the Grevy's zebra, when compared to the congeneric plains zebra, horse, and mountain zebra, allows for this increased investment.