Equus (genus) a female horse. With rare exceptions, these hybrids are sterile and cannot reproduce. A related hybrid, a hinny, is a cross between a male horse and a female donkey. Other hybrids include the zorse, a cross between a zebra and a horse and a zonkey or zedonk, a hybrid of a zebra and a donkey. In areas where Grévy's zebras are sympatric with plains zebras, fertile hybrids do occur. Equines have significant differences in size, though all are characterized by long heads and necks. Their slender legs support their weight on one digit (which evolved from the middle digits). Grévy's
Female cosmetic coalitions will be whether Male B gains sufficient fitness via a roving strategy of picking up cycling, non-cosmetic females. If Male A is not able to compete with Male B in terms of dominance, he is better off choosing the cosmetic females. Because Female B and her non-cosmetic female neighbors get the attentions, but no reliable investment, from Male B, they discourage any investment from the likes of Male A. Once costs of encephalization begin to bite and cooperative strategies are needed to support offspring, how many females will be choosing philanderers in preference to investors? Those females are not likely