Hybrid (biology) are the mule, a cross between a female horse and a male donkey, and the hinny, a cross between a female donkey and a male horse. Pairs of complementary types like the mule and hinny are called reciprocal hybrids. Among many other mammal crosses are hybrid camels, crosses between a bactrian camel and a dromedary. The first known instance of hybrid speciation in marine mammals was discovered in 2014. The clymene dolphin ("Stenella clymene") is a hybrid of two Atlantic species, the spinner and striped dolphins. Cagebird breeders sometimes breed bird hybrids known as mules between species of finch, such
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