Wednesday, August 27, 2008

The language of adolescent mice

Different inbred strains of laboratory mice interact differently, suggesting a role for genetics in social behavior.

They may also speak a different language.

This paper examined behavioral differences between two common strains of mice during adolescence. In the wild, when young mice leave their mothers and head off on their own, they may do so in groups, and the social interactions between individuals in those groups may have survival advantages. The young mice also need to establish territory and find mates. In the study, adolescent C57BL/6 mice had more social interactions than age-matched BALB/c mice. The differences became less pronounced as the mice matured.

The investigators analyzed the mouse vocalizations, even the ones too high for the human ear to detect. (Remember the singing mice?). Vocalization was correlated with social interaction; the socially interactive C57BL/6 mice were more talkative than their BALB/c peers. The C57BL/6 mice also tended to make shorter, higher pitched vocalizations than BALB/c mice.

The investigators found modulations in pitch within each vocalization that reminded me of my disastrous attempt to learn to speak Chinese with all its inflections; upward, downward, complex.

This study also found that the two strains differed in the ways they modulated their vocalizations. For example, BALB/c mice were more likely to use upward modulation and C57BL/6 mice were more likely to use downward modulation.

I wonder if everything the BALB/c mice had to say sounded like a question.