Sexual cannibalism is a phenomenon in nature,many are not familiar with,but it occurs frequently among some species of animals;particularly spiders and snakes.
Sexual cannibalism is the form of cannibalism where an animal of a particular sex devours a member of its own species of the opposite sex,after mating.And this is most often practiced by females,whereby they kill and devour the males after sex.
Spiders and some species of snakes are known for being sexually cannibalistic, though tarantulas (family of large hairy spiders) practice it opportunistically.
Black widow spiders and button spiders sexually cannibalize the males regularly. In these species, the females are way bigger than the males,and a single female can devour one or two males that approach her for sex,after the act is done.
But most often, the second male would survive the sex,because the voracious female would have been full after feeding on the unfortunate first male.
In snakes,Sexual Cannibalism is practised by Anacondas,especially green anacondas,though king cobras can also practice it .
Female green anacondas are the larger sex and regularly devours the smaller male during sex.
For Green Anacondas, sex occurs almost exclusively in water(Anacondas are semiaquatic snakes),and up to twenty males may approach and surround the gigantic female inside the water.They can remain like that for up to two weeks in what is known as Mating Ball.
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