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Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (known as laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings known as hatchlings with little or no embryonic development within the mother.
Oviparity is found in insects, birds. Among mammals, the monotremes are oviparous. Ovo-viviparity: or oviparity with retention of zygotes in either the female's or in the male's body, but there are no trophic interactions between zygote and parents. [1] This mode is found in the slowworm, Anguis fragilis. In the sea horse, zygotes are retained ...
An aphid giving viviparous birth, an unusual mode of reproduction among insects. In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juvenile that is at least metabolically independent.
Gestation, called pregnancy in humans, is the period of time during which the fetus develops, dividing via mitosis inside the female. During this time, the fetus receives all of its nutrition and oxygenated blood from the female, filtered through the placenta , which is attached to the fetus' abdomen via an umbilical cord .
Most reptiles are viviparous, although oviparous reptiles do exist. Oviparous reptiles often display very little or no maternal behavior after the eggs have hatched, while viviparous reptiles typically exhibit more extensive maternal care. [1] Nile crocodiles however, are the exception to this.
Oviparity is typical of birds, reptiles, some cartilaginous fish and most arthropods. Terrestrial organisms are typically oviparous, with egg-casings that resist evaporation of moisture. Ovo-viviparity is where the zygote is retained in the adult's body but there are no trophic (feeding) interactions. That is, the embryo still obtains all of ...
The migratory birds were also considered a delicacy, and the bird, known as the Waldrapp in German, disappeared from Europe, though a few colonies elsewhere survived.
Domesticated birds raised for meat and eggs, called poultry, are the largest source of animal protein eaten by humans; in 2003, 76 million tons of poultry and 61 million tons of eggs were produced worldwide. [288] Chickens account for much of human poultry consumption, though domesticated turkeys, ducks, and geese are also relatively common. [289]