Animals who raise young like humans?

[tremorviolet]

OK, that’s a bad title but I can’t think of something better. It seems to me that most animals will have a litter or a brood and raise them to adulthood before having more. They don’t raise young at different stages of development as humans do. Do any animals ever have young of different ages at the same time? What do chimps and apes do? I can’t think of how to Google this…

[Duck_Duck_Goose]

Well, it depends on how you’re defining “adulthood”. Mares will generally allow their foals to hang around for a year or two until they reach sexual maturity, while they produce Foal #2, and then when Foal #1 reaches sexual maturity, he or she quits hanging around Mom.

But they don’t nurse from Mom all that time–they’re eating grass. They just kind of hang out with her.

As for chimps, they pretty much do it the way humans do it–the kid hangs around for a while and gets to become a “sibling”.
http://www.janegoodall.ca/chimps/chimps_living_sim.html
Put the word “sibling” in your Google searches.

[MikeS]

Crows exhibit such behaviour. From this link:

Most young birds leave their parents soon after leaving the nest, often being chased away, and never see the parents again. In contrast, American crows never chase away their offspring, and the young may remain at home for years. Some crows stay with their parents for up to five years or even longer. (This past year one six-year-old crow that was marked the first year of my study was still associating with its younger siblings and, it appeared, with its unmarked parents.) Probably no crow breeds before it is two years old, and most don’t breed until later than that. While they wait for a breeding opportunity, most crows help their parents raise young. They help feed the incubating female, feed the nestlings and fledglings, defend the territory and the nest, and stand guard over other family members while they forage. Such cooperative breeding behavior is rare in birds. Only a handful of species in North America exhibit it, and none are as widespread as the American crow.

A successful family may raise from one to six young from a nest; the average is three. Two of those three will be alive and with the parents the next year, when they may successfully raise another family. Those two will probably still be with the parents the next year, along with two of their younger siblings. Families quickly become large, with up to 15 crows moving around together.

[percypercy]

Kangaroos do as well. A female kangaroo may have two joeys of different ages. One old enough to follow behind her and one still in the pouch. In such a case the mother is able to produce different kinds of milk for each Joey. Kangaroos also are able to store embryos for several months before they become implanted. This allows for a proper amount of time between the two babies.

http://www.dierinbeeld.nl/animal_files/mammals/kangaroo/
-Lil

[Blake]

Elephants also have a social structure very similar to humans in that the cows have one semi-independent calf at heel and one still suckling. There is also often another adolescent calf from the same cow present in the herd.

As a generalisation humans manage to keep multiple young going at once is because the young are physiologically independent while still being physically and psychologically dependant due to our slow aging process. That means that humans need to keep the young close even after they are weaned. In most other species there is little overlap between weaning and the following partuition so there is no real scope for having multiple young. In species like elephants there is the same extended growth and learning period and the same solution has been found.