Parental investment

Rearing young occurs where the eggs or offspring require looking after, and cannot just be abandoned to fend for themselves as with many species. Care investment may be made before or after birth and the different roles may be carried out by one or both parents. So, for instance, birds need to incubate their eggs and the mother and father often share this duty. Parenting can last for days, months or years with varying levels of involvement by each parent. Sometimes, cooperative breeding takes place where other members of the family assist the parents in looking after the young.

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