How insects learn: the variable and fixed components of bumblebee learning flights

Some bees and wasps leaving their nest for the first time perform elaborately structured learning flights in which they acquire visual information that can guide their return. These learning flights have intrigued many biologists. Almost a century ago Niko Tinbergen observed the learning flights and homing behaviour of wasps that hunt bees and bring them back to nests in sparsely vegetated sand flats. He showed that a single learning flight can be enough for a wasp to learn the visual surroundings of the nest.

We have been working with a ground-nesting bumblebee which also learn very effectively during these flights. Its first trip from the nest may last several hours with the bee remembering what it learnt on departure and returning safely home with a full load of pollen. During their learning flights, bumblebees scan their surroundings; first circling close to the nest entrance and then moving away and towards the nest in a sequence of loops of increasing size. These flights can be stereotyped because both the place from which the insects start, their nest hole, and what they must learn is pre-defined. This close connection between learning and innate patterns of behaviour is characteristic of insects and helps their learning to be rapid.

 Press BB OF 2 JPG

Bumblebee during early phases of the learning flight where it loops and circles closely to the nest.

The pattern of the flights is not entirely fixed, rather it is subtly modulated according to the details of the environment. The ways that bees respond to the systematic manipulation of both local sensory cues and compass cues should reveal some of the behavioural mechanisms that make this unique learning behaviour so effective for acquiring visual and other sensory information.

Dr Natalie Hempel de Ibarra
University of Exeter

Dr Thomas  Collett
University of Sussex

Natalie was awarded a Research Project Grant in June 2012.