Science Focus - the home of BBC Science Focus Magazine

Is cannibalism more natural than we think?

Published: 27th November, 2019 at 14:01
Subscribe to BBC Science Focus Magazine and get 6 issues for just £9.99

It’s one of the last great taboos and a mainstay of horror films. But, as zoologist Bill Schutt reveals, cannibalism is an oft-misunderstood topic.

Why did you decide to write a book about cannibalism?

Most of the books written about cannibalism in the past have either been really sensationalist or aimed at academics. I wanted to write a book that’s somewhere in the middle, a book that’s entertaining and informative but also shows that cannibalism doesn’t always have to be grotesque. There are fascinating and even beautiful aspects to this phenomenon.


Where do we see cannibalism in the natural world?

Cannibalism is natural behaviour across the entire animal kingdom. It’s extremely common in insects and other invertebrates, and in vertebrates like fish and amphibians. It also happens, though far less commonly, in birds and mammals.

The most well-known example is probably sexual cannibalism in spiders, where the females of some species consume the males after mating. From an evolutionary perspective this makes sense – the male is giving the impregnated female a good meal, increasing the likelihood that she will survive and propagate his genes.

Read more:

What other animal species are known to practice cannibalism?

Male lions have been known to eat their rivals’ young, because this brings the lioness back into heat much quicker, so that the male can father his own cubs. It can also be a form of parental care – infant caecilians, a group of limbless amphibians, feed on their mother’s skin – and many bird chicks will eat their weaker siblings.

Then there’s indiscriminate cannibalism amongst fish. Some fish lay millions of eggs, and they won’t necessarily recognise them all as individuals of their own species. Cannibalism is just a way to take advantage of this abundant source of nutrition.

Why do humans sometimes eat each other?

We hear mostly about criminal cannibalism, but I didn’t want to focus on this aspect or glorify it in any way. Instead, I looked at the instances where cannibalism makes more sense. Before it became a Western taboo, it featured in funerary practices in communities around the world – the Fore people in Papua New Guinea would often eat their deceased as an expression of love and grief.

Cannibalism has also served as a food source during sieges and times of famine, and amongst survivors of disasters and strandings. It also used to be widespread in medicine – assorted body parts and blood were consumed for hundreds of years as cures.

Is it still performed anywhere today?

If it is, then it’s done in secret among isolated communities. There are, however, people who still eat their own placentas. This has recently become more popular in the United States: some mothers claim that it helps them feel better by rebalancing their hormone levels post-birth. There’s no scientific evidence for this, so it’s probably a placebo effect, but there probably isn’t any harm in it either.

I even tried it for myself! I was invited to Texas to sample the fresh placenta of a woman who’d just had her 10th child. Her husband cooked it up and it was delicious. I’m not going to reveal what it tasted like, but I will say that it went well with red wine!

Why do you think we’re so disgusted at the thought of cannibalism? 

A lot of it is cultural – there are negative associations in film and literature going all the way from Ancient Greek mythology, through to Shakespeare, the Brothers Grimm and Hannibal Lecter.

But there are also biological reasons. You wouldn’t want to eat your family because you’d be taking your own genes out of the population too, reducing your future chance of evolutionary success (a concept known as ‘inclusive fitness’).

Hannibal Lecter, cinema's most infamous cannibal (YouTube)

Another major drawback to cannibalism is that it involves ingesting parasites and diseases that have already evolved to defeat our immune systems, so it’s not generally a healthy thing to do.

Could cannibalism ever make a comeback?

I think it could. In nature, overpopulation is a primary cause of cannibalism. In humans, combine this with a lack of alternative nutrition – say during an agricultural crisis – and I can see it happening. I’d be mortified, but I wouldn’t be surprised – if you put enough environmental stresses on a group of people, they will turn to cannibalism in order to survive.

Eat Me: A Natural and Unnatural History of Cannibalism by Bill Schutt is out now (£14.99, Profile Books/Wellcome Collection)

Eat Me: A Natural and Unnatural History of Cannibalism by Bill Schutt is out now (£14.99, Profile Books/Wellcome Collection)
  • This article was first published in February 2017


James Lloyd
James LloydStaff writer, BBC Science Focus

James is staff writer at BBC Science Focus magazine. He especially enjoys writing about wellbeing and psychology.


Sponsored content