Neural and Hormonal Basis of Maternal Behavior in the Rat

In many species of birds both the male and female participate in nest building, incubation of eggs, and rearing of the young, and some species are not maternal but parasitic and simply deposit their eggs in the nest of other birds.

Abstract

Maternal behavior encompasses activities concerned with the birth, maintenance, nutrition, and protection of the young. Although the form of these behaviors is closely related to physiological and ecological adaptations of the particular species, the variety and extent of maternal or parental care patterns in various orders of vertebrates is truly astonishing. For example, some viviparous and oviparous species of fish show no maternal interest in their young or eggs, whereas in others, such as the cichlids, the construction of a nest, care of eggs, and protection of young rival in complexity many advanced forms of mammalian maternal care (Noble & Curtis, 1939; Innes, 1966). Reptiles are not known to act maternally toward their young, although oviparous species use protected natural sites or excavate nests for depositing eggs and some show rudimentary incubation of their eggs (Noble & Mason, 1933). In many species of birds both the male and female participate in nest building, incubation of eggs, and rearing of the young. For penguins, which reproduce under relatively adverse climatic conditions, maternal care may be communal activity and a dozen or more adults may take turns at incubation of eggs and feeding of the young. Some species of birds such as the cowbird and cuckoo, are not maternal but parasitic and simply deposit their eggs in the nest of other birds.