THE Nature is beautifulbut it may sound grotesque to us humans. One of the most intriguing practices that happen to some species in the animal world is sexual cannibalism. Practice usually has noble goals, such as being a guaranteeing tactic of Evolution of the species.
In the animal kingdom, sexual cannibalism food is adopted by insectsreptiles, arachnids and cephalopods, such as octopuses, for example. Although there are exceptions, males are usually victims because they are physically smaller in some species.
“In fact, size differences between females and males often determine the frequency of sexual cannibalism, perhaps because the potential to resist a cannibalistic attack is dependent on size,” says Jutta Schneider in his scientific article on the theme.
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Among the reasons behind sexual cannibalism, scientists highlight 4 main reasons. One of them is adaptive forage, when the female gets special nutrients when consuming the male, which can benefit the quality and amount of puppies. Aggressive overflow indicates that the more hostile a female is in its habitat, the more likely to cannibalize a male.
We also have the choice of partner, when females decide on the best male in characteristics, rejecting those they consider weak and inadequate and the case of mistaken identity, when the female eventually confuses the male with a prey for having similar signs.
See below 8 females that kill the males after the copulation
1 – Chironomide mosquito
The female mosquito of the chironomid species is one of the adept insects of sexual cannibalism. The practice is because the male is a very rich nutrient source, and the female needs this food support after mating.
The moment the male is injecting his semen, the female drills the partner’s head causing her death. A curious detail is that it can carry the remains of the male for several days.
2-Praise-to-God
Although sexual cannibalism is a known practice of biologists, for this species it is not a rule. If the female of the mantis is full of stomach, he will hardly think of the male as a meal, even though he is much smaller than her.
But if it is undergoing food shortages, during copulation the female kills the partner through the beheading to feed, since the male is a protein -rich food source. And detail, the male can continue the copulation, even without a head, died only after the coitus.
3 – Black Widow Spider
THE latrodectus mactans He is an old acquaintance of sexual cannibalism. Like other species, making the male your banquet is not a rule either. It varies from food conditions and how much it needs additional energy for egg production.
When females of this species of arachnid kill males, they are looking for protein. In addition, there is another important reason: when killing the male, the female prevents competition for other partners.
4 – Spider Nephila Pilipes
Another adept at sexual cannibalism is the spider Nephila Philipspopularly known as a bourgeois bite, which can be found in bulky forests and gardens.
The female of this species is large in relation to the male and can be 25 to 50 millimeters. Feeding on your partner after coitus is also a practice of food survival.
5-Sucuri-green
Sucuris-green are known to be polyandric, that is, they mate with different males during the reproductive period-which lasts about four weeks. Several males cluster with the female forming the phenomenon known as the “reproduction ball”.
After copulas, the female, which is stronger and more robust than males, chooses one or two partners to make the meal. This is done so that it has more energy stocks to generate eggs, and therefore healthier puppies.
6 – Scorpions
In the case of scorpionssexual cannibalism is not just a reproduction practice, but it is also a matter of survival. Females can generate up to 100 puppies per reproductive period.
And unlike snakes, they are viviparous, that is, embryos do not develop outside the mother’s body, but inside. This generates a much greater energy expenditure, making cannibalism a vital strategy.
7 – Nudibranquios
Nudibranquios are mollusks known as sea slugs. Hermaphrodites, they can produce both eggs and sperm, but they cannot self -care, needing a partner for it.
The copulation happens through the eviction of a sperm mass in a slit located on the anterior part of the body of one of the nudibranchia. After fertilization, thousands of eggs are released into the water. In the case of nudibranchia with horns, after coitus can be cannibalized of one animal by the other.
8 – Octopus
The female of the octopus-of-the-amly-azuis species (Maculosa Hapalochlaena) It also uses the male after the copulation as a meal. After placing the eggs, she spends six weeks without feeding the puppies, so this stock of energy needs to come from a nearby source. But this species holds an interesting evolutionary twist.
After much died in the tentacles of their partners, the Male of the Octopus Objects has developed a strategy to reproduce without dying. During the copulation, he bites the female’s aortry artery injecting tetrodotoxin, a kind of sedative poison that leaves the female immobilized during coitus.
Second study published in the magazine Currenty Biologymale poisoning is done in a calculated manner, so that the next day the females are already feeding normally – which indicates a certain resistance to the injected toxin.
