Many species kill each other, often when the baby is sick, deformed, or born when the mother is unable to produce milk or provide other food. If a baby dies or does not survive, its body can be a valuable source of nutrition for parents. This is often referred to as cannibalism.
Species that cannibalize include leopards, African lions, tonkya macaques and many fish.
This form of cannibalism can also occur much earlier, such as when the offspring are eggs. Eating eggs is easy, nutritious, and effortless to eat.
A cod is laying 5 million eggs, so that the eggs are sometimes a delicious delicacy for the mother fish and are very nutritious.
Female snappers from Central Africa often have eggs in their mouths. Surprisingly, a recent study showed that these fish mothers sometimes eat more than three-quarters of their eggs and baby fish.
In other species, males usually kill babies who have nothing to do with themselves, an act known as infanticide. For example, in North American red squirrels, males kill and eat pups that do not belong to him or whose parent-child relationship is uncertain. In this way, the female will re-enter estrus, ready to mate again quickly. In this way, the male can protect the female from other mating, ensuring that the cub is his. Lions and chimpanzees also kill infants.
In other species, siblings will attack each other for a chance to survive. Black-footed toads are known to lay their eggs in ponds that dry up rapidly. Some tadpoles will grow larger heads, wider mouths, and sharper teeth than their siblings. These tadpoles will then eat their kind, helping them grow quickly.
Overcrowding is most likely to stimulate cannibalistic behavior. When a species has a relatively low density and has enough food, they generally do not attack each other.
Some species do not wait until after birth to start eating siblings. Female sharks have hundreds of eggs in both wombs, mating with multiple males and producing offspring from multiple fathers. In the womb, developing sharks eat the remaining unfertilized eggs, eventually eating their embryonic siblings, a behavior known as intrauterine cannibalism. Eventually there were only two unborn sharks left, one in each womb, which made them hunters by nature.
Die to survive
Spiders also adopt another form of cannibalism, mother-eating, in which newborn spiders eat their mothers. In the last act of motherhood, the velvet spider will dissolve her organs and vomit them for the offspring to eat, and finally they will eat her entire body.
The last organs liquefied are her heart and ovaries, which is an insurance measure to ensure that if a male spider eats her baby, she can mate with him and try again. (Watch the little spider devour mom alive.) )
Many insect or arachnid fathers never live to see their offspring. In a form of sexual cannibalism, females eat all or part of their male partner during or after mating.
Male Australian redback spiders are often eaten by larger and more mature female spiders. Some will even twist their bodies to allow their bodies to be pierced by her fangs, which not only provides a healthy meal for the expectant mother, but also increases the chances of his offspring surviving.
Also cannibalized are female wormwood crickets, which bite the back wing of males during mating and drink their nutrient-rich blood, known as hemolymph. It is an attempt to make it impossible for a male to mate with another female again.
The European female mantis bites off the male mantis even before it begins mating. But males have evolved a new way of mating, and even if they are headless, male praying mantises' sexual behavior is controlled by abdominal tissue. The sacrifice of the male is beneficial not only for the health of the female, but also for the number of female offspring.
For many animals, cannibalism is beneficial. It also has disadvantages, such as spreading diseases.
