Question

Among mammalian species, male fitness is typically more variable than female fitness. Explain why this is often the case. What implications does this have for evolution acting on males and females?

Answer 1

Among mammals, male fitness is typically more variable than female fitness. It is because males have more competition among themselves to grab more opportunities for mating. As such the males which are physically more fit, robust and long life span have more advantages of fertilizing more females. Thus the result is, such males will have more offsprings through different females. As per Bateman, such males will be selected by nature. Whereas females can't mate with more males at the same time and therefore do not exhibit much variation in fitness. The fitness variability in males results in evolution favoring such males which reproduce more on account of their more fitness.