Cannibalism in snakes might sound strange, but it’s more common than you think. A recent study found that this behavior has evolved in snakes at least 11 times throughout history, often due to environmental pressures.
Researchers analyzed 500 reports of cannibalistic behavior in various snake species, revealing that cannibalism is not just a fluke; it happens when snakes face food shortages or specific ecological challenges. Bruna Falcão, a biologist from the University of São Paulo, explains, “For snakes, cannibalism can actually improve their chances of survival.” In contrast, humans typically view cannibalism as abhorrent.
Interestingly, cannibalism is observed in many animal groups, including spiders and praying mantises. Experts like Xavier Glaudas, a biologist and National Geographic Explorer, note that cannibalism might not be maladaptive in some cases. It could help animals manage resources better, control their populations, or feed on available prey. This flexibility serves as a survival strategy, especially during tough times.
The study included 503 documented cases across 207 different species of snakes, covering all continents except Antarctica. Most were seen in the Colubridae, Viperidae, and Elapidae families. Colubridae, which includes non-cannibalistic species as well, constituted about 29% of reports, while Viperidae represented 21%, mostly in captivity. Elapidae, home to cobras, accounted for around 19%. Because some species in these families typically don’t eat other snakes, researchers suggest these behaviors might stem from stress, like food scarcity or confinement.
Recent data show that about half of the cannibalistic snake species have flexible diets, making it easier for them to adapt. However, Glaudas expressed caution about linking generalist diets directly to cannibalism, indicating that the evidence is not entirely conclusive. Interestingly, the ability to consume another snake often depends on jaw structure; species with wider jaws are more likely to exhibit cannibalistic behavior.
As this study indicates, cannibalism is a widespread phenomenon in snakes, happening in various contexts and situations. The adaptability of snakes in changing environments sheds light on their evolutionary success. Falcão notes how fascinating it is that such a behavior has emerged independently multiple times: “It’s really surprising for cannibalism to evolve 11 times in snake lineages.” This piece of research opens the door for further exploration into the intriguing world of snakes.
For more detailed information on this study, you can check the source published in Biological Reviews.
