Time-telling bumble bees

The findings of Psychology professor David Sherry and PhD student Michael Boisvert broaden the understanding of time perception in the animal kingdom.

Many insects have shown daily and annual rhythms of behaviour, but the more sophisticated ability to estimate the duration of shorter time intervals had previously been known only in humans and other vertebrates.

Details of the research are published as the cover story in the August 22 issue of the journal Current Biology.

Bees and other insects make a variety of decisions that appear to require the ability to estimate elapsed durations, the research finds.

Insect pollinators feed on floral nectar that depletes and renews with the passage of time, and insect communication and navigation may also require the ability to estimate the duration of time intervals.

In their work, Sherry and Boisvert investigated bumble bees' ability to time the interval between successive nectar rewards. Using a specially designed chamber in which bumble bees extended their proboscis to obtain sucrose rewards, the researchers observed that bees adjusted the timing of proboscis extensions so that most were made near the end of the programmed interval between rewards.

When nectar was delivered after either of two different intervals, bees could often time both intervals simultaneously. This research shows that the biological foundations of time perception may be found in animals with relatively simple neural systems.

This research is part of a doctoral dissertation by Boisvert and was supported by a grant from the Natural Science and Engineering Research Council of Canada to Sherry.

For more on their research, visit: www.current-biology.com