Small or large families?

It is not only humans who deal with this problem, but other animals also choose different ways to maintain their families. Some choose to care for their offspring as best they can every few years, while others choose a strategy where only the most viable offspring survive.
ležící zajíc
Not all offspring have a chance of survival, and only one can survive
A female North American opossumcan have up to 16 young per litter. Trouble is, she has only 13 nipples, so it is a foregone conclusion that she cannot have all her babies. Moreover, some of the nipples do not produce milk. All marsupial newborns must be firmly attached to the mammary glands. A baby opossum is about the size of a honeybee, and after birth it climbs up its mother\’s abdomen and enters the pouch, where it stays for about two months. If they arrive later than their siblings, they die, and usually no more than eight survive. This allows only the strongest to survive. However, if only one embryo enters the pouch, it also has little chance of surviving because it does not suckle enough milk to stimulate milk production.
vačice na stromě
Oysters lay as many as 500 million eggs a year! [It\’s hard to find a more different species than this. Orangutans have a baby every 6 years on average. On the other hand, oysters can lay as many as 500 million eggs per year. Some fish lay as few as 100 eggs and deposit them in carefully constructed nests among coral and algae, which are defended to increase the chances of survival of their offspring. Sea hares, on the other hand, lay a million eggs, which drift freely throughout the ocean. It is clear that most of them do not hatch; orangutan v zoo
orangutan v zoo
breeding like a hare can be dangerous

North American female hares can reach sexual maturity in three months and can leave up to 30 offspring per year. A well-known example is the European hare introduced to Australia, which reproduced so rapidly because of the lack of natural enemies in Australia. North American voles can produce up to eight litters per litter and up to 17 litters during the breeding season. If all of these offspring survive, the earth will soon be overrun with voles. Fortunately, this is not the case, and only about two-thirds of the population survives for two months. Vultures are favorite prey of snakes, weasels, owls and predators. Furthermore, intraspecific aggressive behavior occurs when overpopulation is threatened.