Snakes Resort to Cannibalism When the Opportunity Strikes, Study Shows

Scientists have uncovered yet another reason not to trust a snake—the slithering creatures have a habit of eating each other.

A recent study compiled over 500 incidents of cannibalism in more than 200 species of snakes, revealing that the behavior is much more common than believed. Snakes are likely to feed on one another due to opportunistic choices, sometimes driven by limited food sources or environmental stressors.

The study, published in Biological Reviews, offers the first comprehensive overview of cannibalism in snakes and suggests that the behavior has repeatedly come up during the evolutionary history of the carnivorous reptiles.

Legless Hannibal

Cannibalism in snakes has only been reported in isolated incidents, but the researchers behind the study were curious to observe patterns of the behavior.

For the study, a team of researchers from Brazil spent two years examining peer-reviewed studies, books, and magazines to collect sightings and anecdotes of snakes eating each other. The researchers divided the cases into different types of cannibalism, such as ones that occur between mating pairs, adversaries, or snakes within the same family.

The review found that cannibalism may have sprung up independently at least 11 times during the evolutionary history of snakes. Some of the incidents were driven by scarcity of food, with snakes feeding on one another as a form of last resort. Other incidents occurred in captivity, where confinement and a limited food supply drove snakes to cannibalism.

The incidents spanned across different snake species. Elapids, the snake family that includes cobras, accounted for around 19% of the cannibalistic incidents. On the other hand, blind snakes were the only major group not included in the recorded events. That’s most likely because this particular group of snakes never evolved the unfused lower jaw that would allow them to open up wide enough to swallow another one of their own.

Snakey behavior

The recent study is a comprehensive look at cannibalistic behavior among snakes, but there are likely many more incidents that have gone unrecorded.

Overall, this initial glimpse into the world of the sneaky reptiles allows scientists to better understand the behavior of snakes, and the lengths they will go to survive in less-opportune circumstances.