SCHLEICH Cristian Eric
Do subterranean mammals use the Earth’s magnetic field as a heading indicator to dig straight tunnels?
MALEWSKI, SANDRA; BEGALL, SABINE; SCHLEICH, CRISTIAN E.; ANTENUCCI, C. DANIEL; BURDA, HYNEK
Año: 2018 vol. 6
Subterranean rodents are able to dig long straight tunnels. Keeping the course of such?runways? is important in the context of optimal foraging strategies and natal ormating dispersal. These tunnels are built in the course of a long time, and in socialspecies, by several animals. Although the ability to keep the course of digging hasalready been described in the 1950s, its proximate mechanism could still not besatisfactorily explained. Here, we analyzed the directional orientation of 68 burrowsystems in five subterranean rodent species (Fukomys anselli, F. mechowii,Heliophobius argenteocinereus, Spalax galili, and Ctenomys talarum) on the base ofdetailed maps of burrow systems charted within the framework of other studies andprovided to us. The directional orientation of the vast majority of all evaluatedburrow systems on the individual level (94%) showed a significant deviation from arandom distribution. The second order statistics (averaging mean vectors of allthe studied burrow systems of a respective species) revealed significant deviationsfrom random distribution with a prevalence of north?south (H. argenteocinereus),NNW?SSE (C. talarum), and NE?SW (Fukomys mole-rats) oriented tunnels. Burrowsystems of S. galili were randomly oriented. We suggest that the Earth?s magneticfield acts as a common heading indicator, facilitating to keep the course of digging.This study provides a field test and further evidence for magnetoreception andits biological meaning in subterranean mammals. Furthermore, it lays the foundationfor future field experiments.