Public lecture explores navigational wonders of the insect world

Anyone who has watched a fly make a flawless landing on the rim of a teacup, or marvelled at a honeybee speeding home after collecting nectar from a flower patch several kilometres away, would know that insects possess visual systems that are fast, reliable and accurate.

Insects cope remarkably well with their world, despite possessing a brain that carries fewer than 0.01 percent as many neurons as ours does.

Dr Mandyam V. Srinivasan of the Centre for Visual Sciences, Research School of Biological Sciences, Australian National University (ANU) will explore these capabilities at a public lecture at the Brisbane Convention Centre on Monday, January 29, 2001.

The talk, to be held in the Great Hall between 6pm and 7pm, will reveal the secrets of insects' success by describing research aimed at understanding the mechanisms underlying visual perception, navigation, learning, memory and "cognition" in honeybees, and comparing these with human performance.

Insects use a number of ingenious strategies for perceiving their world in three dimensions and navigating successfully in it. Distances to objects, for example, are gauged in terms of the apparent speeds of motion of the objects' images, rather than by using complex stereo mechanisms.

Objects are distinguished from backgrounds by sensing the apparent relative motion at the boundary between object and background. Collision-free flights through narrow gaps are achieved by balancing the image velocities experienced by the two eyes.

Flight-speed is regulated by holding constant the average image velocity as seen by the two eyes. Smooth landings on a horizontal surface are orchestrated by holding the image velocity of the surface constant as it is approached, thus automatically ensuring that flight speed is close to zero at touch-down.

Foraging bees gauge distance flown by integrating the optic flow experienced en route: they possess a visually driven "odometer" that is robust to variations in wind, body weight and energy expenditure.

Honeybees can be trained to detect camouflaged objects and to display associative recall. They can learn to use symbolic signposts to navigate complex mazes.

The opportunities for incorporating insect-based principles into the design of novel, autonomous robots will also be briefly discussed.

For more information, contact M.V. Srinivasan (telephone 02 6125 2409 at work, 02 6258 6038 at home or in Brisbane at the Park View Motel on 07 3846 2900), Associate Professor Brian Key (mobile 0413 008 458) or Shirley Glaister at UQ Communications (telephone 07 3365 2339).