Vocalization Helps Gray Mouse Lemurs to Avoid Inbreeding

Gray mouse lemurs are able to recognize paternal relatives using vocal communication, reveals a new study.

The finding defies the earlier belief that only large-brained animals with complex social groups could recognize the calls of paternal kin, which helps them to avoid inbreeding.

Gray mouse lemurs (Microcebus murinus) are small-brained animals that are commonly found in Madagascar. Vocal communication plays a significant role in this particular species, as vision is poor and identifying other members using smell is limited.

The females of this species remain in the same place after giving birth to offspring. They raise the young ones with other female kin. Males do not stay with their mates nor give any parental care to the offspring. Hence, vocalization is important for these lemurs to socially interact with their family, in particular, to avoid inbreeding.

A team of researchers from the Arizona State University and the University of Veterinary Medicine Hannover in Germany found that the mouse lemurs make two types of calls - mate advertisement calls and alarm calls.

When the research team analyzed the acoustic parameters in both types of calls, they noticed that the calls had different signatures. They found that the male gray mouse lemurs had acoustic paternal signatures in their advertisement calls. 

Experts also noticed that the females paid more attention to advertisement calls from unrelated males than from their fathers. This way, the lemurs were able to avoid inbreeding.

They also suggested that the lemurs might be using alarm calls, where they make ultrasonic calls above the hearing range of owls, as an anti-predator strategy.

"Given that more complex forms of sociality with cohesive foraging groups are thought to have evolved from an ancestral solitary forager much like the mouse lemur, this suggests that the mechanisms for kin recognition like those seen here may be the foundation from which more complex forms of kin-based sociality evolved," Sharon E. Kessler, from the Arizona State University, said in a statement.

Kessler and her colleagues will be studying further to determine which acoustics parameter helps in recognizing calls from kin "by artificially manipulating acoustic parameters in the calls and then using the modified calls in playback experiments."

The findings of the study, "Paternal kin recognition in the high frequency / ultrasonic range in a solitary foraging mammal", are published in the journal BMC Ecology.