Reaction to New Objects and Spatial Changes in Young and Aged Grey Mouse Lemurs ( Microcebus murinus )

Abstract

The exploratory behaviour of young and grey mouse lemurs (Microceb11s murinus) in an experimental enclosure containing various objects was recorded. A new object was added for each test session and could displace an object that had previously been introduced to a new position. For young grey mouse lemurs, there was an obvious preference for new objects and for displaced familiar objects. This indicates that they are able, like other primates, to “map out” and memorize their environment. For the aged grey mouse lemurs, preference for the new objects was very slight. No react ion to changes in the location of familiar objects was noted. Age- related deficits in memory, in particular spatial memory, could account for this lack of response to changes in the environment.