Sniffing behaviours in guenons.

Area of Science:

• Primatology
• Ethology
• Sensory Ecology

Background:

• Old World monkeys (OWM) were traditionally considered to have a less developed olfactory sense compared to other primates.
• Recent research indicates OWM possess more advanced olfactory capabilities than initially assumed.
• Understanding olfactory behavior is crucial for assessing sensory ecology in primates.

Purpose of the Study:

• To investigate and quantify sniffing behaviors in three guenon species for the first time.
• To compare olfactory sense usage across closely related primate species.
• To explore potential drivers, such as natural selection, behind observed differences in olfactory behavior.

Main Methods:

• Observational study of three guenon species (Diana, de Brazza's, and owl-faced monkeys) at Leipzig Zoo.
• Recording the frequency and contextual occurrence of sniffing behaviors.
• Calculating a 'sniff index' for standardized interspecies comparison.

Main Results:

• OWM individuals exhibited an average sniffing frequency of 6.12 ± 7.69 times per hour.
• Sniffing behavior was predominantly observed in food-related contexts.
• Diana monkeys demonstrated significantly less frequent sniffing compared to de Brazza's and owl-faced monkeys.

Conclusions:

• The study highlights that olfactory capabilities in OWM are more nuanced than previously understood.
• Observed variations in sniffing frequency among guenon species suggest differential reliance on the olfactory sense.
• Natural selection may play a role in shaping the distinct use of olfactory senses within closely related primate lineages.