Chemical cues benefit young beetles

Young beetles pick up sensory signals from adult insects to improve their chances of survival, University research shows.

A study of burying beetles has shown that chemical cues allow larvae to distinguish between adults likely to provide food and those that will ignore or attack them.

Larvae have an in-built ability to identify different adults based on distinct chemicals found on the outside of their shells and adjust their begging behaviour accordingly, researchers say.

Selective begging

Adult beetles bury and feed upon the carcasses of small birds and rodents to provide their young with food. They regurgitate the pre-digested flesh for larvae when they beg to be fed.

The research shows that larvae can distinguish between breeding and non-breeding adults.

They beg from breeding beetles but avoid non-breeding adults, as these tend to view the larvae as potential competition for their own unhatched young and kill them.

Maximising benefits

The study of a species called Nicrophorus vespilloides also reveals larvae do not discriminate between male and female parents when they beg as both adults will feed them if prompted.

The team found that larvae opt to beg for food from unfamiliar beetles over familiar ones.

Researchers say larvae may instinctively beg more from adults unknown to them, which could benefit young beetles by increasing the amount of resources they receive as they grow.

Complex behaviours

Mature burying beetles are known to distinguish between adults based on the chemical make-up of their shells.

The team’s evidence is the first to show that larvae share the same ability.

The study is published in the journal Ethology.

Our results show that larvae have the ability to recognise their parents, and they use it selectively to their advantage. It is an exciting result shedding more light on the mechanisms behind the complex behaviours exhibited by these beetles.

Maarit MäenpääSchool of Biological Sciences