What is Bateman's principle?Bateman's principleLots of spermFeweggsSperm must compete over eggsVria iepaduivesc ie mudigae in males tanin female The vane isame ete emity of saelecionMales must compete overfemalesLots of spermFeweggsATerrnitoral males direct more courtship dispiays towardsfemales that have shown up on their teritory for the firsttime compared to long term females companions.Males must maimce the number of matesPreferencefor "new femalesA single bird eggmay constitute 15-20%of female's body massLots of spermFew eggsFemales must maimize reproductivesuccess per eggCS Scanned with CamScanner

Bateman's Principle: In evolutionary biology, Bateman's principle states that in most species, males have more variability in reproductive success (or reproductive variance) than females. Angus John Bateman (1919–1996), an English geneticist, was the first to propose it. Bateman theorised that, because males can produce millions of sperm cells with minimal effort, while females must expend much more energy to nurture a relatively small number of eggs, the female has a much greater impact on the reproductive success of their progeny. According to Bateman's Principle, females are the limiting factor of parental investment, and males will fight for their attention in order to copulate successfully.Bateman's principles explain sex roles and sexual dimorphism by examining sex-specific differences in mating success, reproductive success, and their interrelationships (Bateman gradients).