The Physiological Effects of Cannibalism

The practice of cannibalism, which involves an animal eating members of its own species, is rare in human civilizations, but more common in other animals. While not much scientific research has been done on the physiological effects of cannibalism, scientists who have studied this phenomenon have found that the risk of parasites and pathogens is increased in cannibals, as is the likelihood of illness and growth problems.

Benefits

• Theoretically, cannibalism could have many benefits for an organism or species. Since members of a species share biological and chemical compositions, an organism or animal that eats a member of its own species would absorb nutrients essential to its own survival. For example, if an insect eats another insect of the same species, it would absorb the proteins present in the body of the other insect to use for its own biological processes.

Survivability

• Cannibalism can also be used to control a population and to prevent predators from feeding on deceased members of a species. In nonhuman species in particular, the practice of cannibalism has played a role in evolutionary biology. For example, a species dealing with limited resources due to overpopulation might begin to cannibalize itself in order to ensure enough food remains for continued survival. A species might also practice cannibalism to prevent competing species from benefiting from eating its dead.

Disease Transmission

• The major physiological issue with cannibalism is the transmission of disease. Some diseases are more easily transmitted among members of the same species than between species, and the practice of cannibalism means that any disease present in the food source has a higher chance of being transmitted to the organism that eats it. For example, the brain disease kuru likely spread among cannibals in New Guinea because of the consumption of an individual with the disease.

Bacteria Consumption

• Another physiological risk of cannibalism is the unintended consumption of foreign matter present in the body of the organism being eaten. For example, a mammal that eats the intestines of another member of its species risks consuming fecal matter present in the intestinal tract, increasing the risk of diseases like E. coli. This risk is closely linked to the risk of diseases transmitted between members of the same species, since bacteria present in one member of a species can easily move to another member of the same species.