Researchers studying the innocuous-seeming fruit fly have found that the insects have cannibalistic tendencies.

In "crowded laboratory conditions", the larvae, or maggots, will often pursue, attack and eat one another, footage reveals.

Scientists investigating the effects of malnourishment on the flies found that they were able to rear keener, more capable cannibals.

The findings are reported in the journal Nature Communications.

Here, lead researcher Roshan Vijendravarma from the University of Lausanne explains what his gruesome discovery reveals, and why cannibalism remains something of a biological mystery.

Footage courtesy of the University of Lausanne