Let’s return to explore more Nightmarish Nature, shall we? This segment focuses on cannibalism, as we generally find it icky / taboo and because it’s more common than you might think. There are many different reasons that different creatures engage in cannibalistic practices. Energy waste doesn’t last long in nature; gaps are filled as things evolve to utilize whatever resources are available to meet their own needs. C’est la vie (light up another cigarette). In any case, the challenge to the cannibal lies in determining kinship and not accidentally erasing their own line or progeny, thus decreasing their likelihood for survival over generations. Oh, and in avoiding those pesky prion diseases…

Resource Driven Cannibalism

Resource driven cannibalism can occur when competition for resources is high. This may be due to scarcity, with individuals taking to eating each other to avoid themselves starving to death (with those consumed either still alive and killed to this end, or eaten after death of other causes). Or it may be outside of the cannibal’s control, considering the spread of Mad Cow Disease from feeding beef meal harboring the prion disease (and parts from other mammals like sheep) to growing cattle to save money, ’cause it’s not like the cows were allowed to order whatever they wanted. Or it may be due to direct conflicts with other groups of the same species, either due to competition for resources, mating rights and/or territory. These behaviors have been noted in mostly male chimpanzees raiding other groups, which have even been documented as all out wars against other males in neighboring bands, campaigning to eradicate all outside of their ranks.

Social Demonstration

Thinking about chimpanzees, males are also documented to gang up on alpha males seen as too controlling or sadistic, with groups of younger males attacking and rendering the alpha male to pieces, often consuming his flesh and blood in the process. This can upend established hierarchies to replace them with new structures, for example with a new male taking on the role of leader. But cannibalism can also be used to reinforce existing hierarchies, as seen in African Wild Dogs wherein the dominant pair will kill off any offspring that other dogs may have birthed so that the pack will focus on raising only the alpha pair’s pups, thusly reestablishing and enforcing social structure while ensuring the best survival chances for the pups raised by channeling all resources to the one brood.

Infanticide & Filial Cannibalism

Like African Wild Dogs, other parents may also eat their offspring, or better yet their rivals’ offspring. Stillborn or unhealthy offspring may be consumed, or just any that they can get their hands on at birth. (Again with the young male chimpanzees…) Some creatures enter into cycles wherein smaller individuals are more vulnerable to predation by larger ones both within and outside of ones own species, as is seen among many fishes with eggs and smaller fishes playing an important role as prey to larger ones. Other creatures may engage in these practices to reduce competition (for themselves and/or their offspring) and/or increase opportunities to mate. Male cats are notorious for killing kittens that are not their own in order to bring females into heat again sooner, potentially increasing the likelihood of mating with said females themselves while decreasing future competition. Win-win! Female cats must take great care to hide their kittens in order to protect them from males as much as other predators, and can have kittens by different fathers within the same litter in order to increase their kittens’ overall survival as a group with father cats more willing to accept kittens when their own kin are present.

Sexual Cannibalism

Mantids and spiders are especially known for sexual cannibalism, with larger females consuming males during copulation, but this is not always linked to vast size differences and does not appear in every species. Females who engage in this practice may have healthier eggs in larger clutches, thus increasing the survival likelihood of more of their offspring. Sometimes the risk to the male suitor of being mistaken for another species by an aggressive would-be mate is high, and various rituals have developed within certain species to help avoid such mistakes and entice the female to mate. Male spiders are known engage in elaborate dances, movements, tapping and silk spinning rituals to avoid being eaten pre-copulation or at all. It’s a hell of a lot more involved than a good pick up line and a well-timed drink, as you can see here.

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Thank you for joining us for another exciting episode of Nightmarish Nature. If you enjoyed this, please feel free to check out these previous segments:

Vampires Among Us

Perilous Parenting

Freaky Fungus

Worrisome Wasps