Search results
Results From The WOW.Com Content Network
Another example is Lasioglossum hemichalceum, which is a species of sweat bee that shows drastic physical dimorphisms between male offspring. [34] Not all dimorphism has to have a drastic difference between the sexes. Andrena agilissima is a mining bee where the females only have a slightly larger head than the males. [35]
In biology, offspring are the young creation of living organisms, produced either by sexual or asexual reproduction. Collective offspring may be known as a brood or progeny . This can refer to a set of simultaneous offspring, such as the chicks hatched from one clutch of eggs , or to all offspring produced over time, as with the honeybee .
Azaras's capuchin or hooded capuchin (Sapajus cay) is a species of robust capuchin. It occurs in eastern Paraguay, southeastern Bolivia, northern Argentina, and Brazil, at Mato Grosso do Sul and Mato Grosso states, in Pantanal. Its habitat consists of subtropical, humid, semi-deciduous, gallery forests and forested regions of the Pantanals.
Male development can only occur when the fetal testis secretes key hormones at a critical period in early gestation. The testes begin to secrete three hormones that influence the male internal and external genitalia: they secrete anti-Müllerian hormone (AMH), testosterone, and dihydrotestosterone (DHT). Anti-Müllerian hormone causes the ...
Sexual differentiation is the process of development of the sex differences between males and females from an undifferentiated zygote. [1] [2] Sex determination is often distinct from sex differentiation; sex determination is the designation for the development stage towards either male or female, while sex differentiation is the pathway towards the development of the phenotype.
An acquired characteristic is a non-heritable change in a function or structure of a living organism caused after birth by disease, injury, accident, deliberate modification, variation, repeated use, disuse, misuse, or other environmental influence.
Bateman attributed the origin of the unequal investment to the differences in the production of gametes: sperm are cheaper than eggs. A single male can easily fertilize all of a female's eggs; she will not produce more offspring by mating with more than one male. A male is capable of fathering more offspring if he mates with several females.
Sexual selection is an evolutionary concept that has been used to explain why, in some species, male and female individuals behave differently in selecting mates. In 1930, Ronald Fisher wrote The Genetical Theory of Natural Selection, [3] in which he introduced the modern concept of parental investment, introduced the sexy son hypothesis, and introduced Fisher's principle.