What is the point of pigeons

UZH News

anatomy

How do carrier pigeons find their way home? Hans-Peter Lipp and Nicole Blaser from the Anatomical Institute of the UZH let birds fly over a meteorite crater in the Ukraine. The experiment shows that pigeons have a sense of the finest differences in gravity and use this for orientation.

Adrian Knight

Fine sensorium: carrier pigeons are able to perceive the finest differences in gravity. (Image: Andreas Trepte / photo-natur.de)

Carrier pigeons find their way home from an unknown place. They are based on geomagnetism, the stars and the position of the sun. But not only, as a recently published study in the Journal of Experimental Biology shows. Hans-Peter Lipp, emeritus professor of anatomy at the UZH, and his doctoral student Nicole Blaser, together with other researchers, show that pigeons also have a sense of the strength of gravity.

The gravitation changes depending on the height above sea level, but also depending on the subsurface of the earth. Pigeons have a kind of "gyroscope" - a measuring device that is used in navigation. This enables them to perceive the difference between the gravity at the place of their release and in their home attack. From this they deduce the direction of flight home.

Flight over the crater

With an experiment, the researchers were able to show that gravity actually plays an important role in the orientation of the pigeons. They let 26 pigeons equipped with GPS fly over a meteorite crater in the Ukraine. The crater is 25 kilometers in diameter and has an exceptionally low gravity.

Accordingly, this confused the pigeon's navigation system. An above-average number of pigeons struggled to find their way home across the crater - compared to a control group of birds that started further away from the crater.

Now Hans-Peter Lipp wants to investigate the cellular mechanisms with which pigeons can perceive the finest differences in gravity.

Adrian Ritter is editor of UZH News.