Experimental evidence for olfactory predator recognition in wild mouse lemurs

Abstract

Although primates have remarkable olfactory capabilities, their ability for olfactory predator recognition is still understudied. We investigated this cognitive ability in wild gray and golden-brown mouse lemurs (Microcebus murinus and M. ravelobensis) that were confronted with four different olfactory stimuli, derived from two Malagasy predators (fossa and barn owl) and two local nonpredator species (brown lemur and sifaka). The predator response was tested (1) in a systematic cage setup and (2) in a two-way choice experiment with two Sherman traps on platforms in the forest (stimulus trap vs. nonstimulus trap). For part 1, the study animals were housed in cages during habituation and 5 days of experiments. One stimulus was tested per night and was presented underneath a drinking bottle. The changes in the time spent close to the stimulus and the drinking time at the bottle were used as indicators of predator recognition. A timidity score was established by classifying the strength of the antipredator response during the experiment. The study animals spent significantly less time drinking and less time in the stimulus area when confronted with fossa odor compared with the other stimuli. The timidity score was significantly higher during the fossa stimulus compared with the nonpredator and the control stimuli. The two-way choice experiments revealed a complete avoidance of the fossa odor, which was not found with the other stimuli. Thus, wild mouse lemurs showed clear signs of olfactory predator recognition in the case of the fossa in both experiments, but no signs of avoidance to the other presented stimuli. The lack of owl avoidance may be explained by less or no aversive metabolites in the owl stimulus or by lower significance for olfactory recognition of aerial predators. Furthermore, the results showed slight differences between the two mouse lemur species that may be linked to differences in their ecology. Am. J. Primatol. 73:928-938, 2011.

First evidence for functional vomeronasal 2 receptor genes in primates

“…In addition to intraspecific communication, mice can also detect MUPs from predators using V2Rs [2,20]. It is known that mouse lemurs react to olfactory cues from predators [21,22] and females exercise post-copulatory mate choice based on MHC constitution [23]. Given their conservation over millions of years of evolution and the importance of pheromonal communication in strepsirrhines [24], we can speculate that the intact V2Rs in strepsirrhines likely have an rsbl.royalsocietypublishing.org Biol Lett 9: 20121006 important role in pheromone detection.…”

Response Behaviors of Svalbard Reindeer TOwards Humans and Humans Disguised as Polar Bears on Edgeøya

“…They concluded that fear in seals is focused on local threats by learning and experience. The predator recognition may be olfactory, acoustic, and visual (Blumstein et al, 2000;Deecke et al, 2002;Webb et al, 2010;Kappel et al, 2011). Since there were no olfactory or acoustic stimuli in our study (head wind and no noise from the observer apart from normal walking noise during all approaches), predator recognition must have been associated with the visual image of the encountering object.…”

Hearing and Age-Related Changes in the Gray Mouse Lemur

“…Thus, an adaptation to predator avoidance seems to be more likely. Mouse lemurs face the highest predation risk in primates (Scheumann et al 2007) and mostly rely on olfactory and acoustic cues for predator detection and avoidance (Kappel et al 2011;Rahlfs and Fichtel 2010;Sündermann et al 2008). An important predator of mouse lemurs is the Madagascar harrier hawk (Polyboroides radiatus) (Fichtel and Kappeler 2002), and indeed, the frequencies of its vocalizations overlap with the mouse lemur's best frequency of hearing.…”

“…Besides the importance of the gray mouse lemur for biomedical research, mouse lemurs are also important for evolutionary research since they model the ancestral primate condition (Kessler et al 2014;Martin 1972;. Mouse lemurs resemble ancestral primates in being small, nocturnal, and living in dispersed social systems in dense forest environments where they rely mainly on olfactory and acoustic cues for social communication (Buesching et al 1998;Perret 1995;Zimmermann 2010) and prey and predator detection, localization, and recognition (Bunkus et al 2005;Goerlitz and Siemers 2007;Kappel et al 2011;Piep et al 2008;Siemers et al 2007;Sündermann et al 2008).…”