Quantitative aspects of vocal communication – such as how frequently animals vocalize – vary between and within species. According to the ‘vocal grooming hypothesis,’ time budget pressures constrain variation in vocalization rates. Some species need efficient strategies to interact with others while engaging in other activities. Specifically, animals living in affiliative groups may compensate for time constraints by socializing through vocal exchanges. Many species produce simple ‘contact call’ vocalizations when they are separated from others. These patterns suggest that gregarious social systems co-evolved with an increased reliance on vocalizations to promote cohesion. Whether these patterns apply to species living in small, yet highly affiliative, social groups is unclear.

Current projects in the lab investigate the role of vocalizations in pair bond maintenance in prairie voles (Microtus ochrogaster). We are exploring how the usage of prairie vole vocalizations relates to short and long-term measures of pair bond strength. Methods that we use include behavioural tracking, acoustic recording, and playback experiments.