See You Next Summer

See allHide authors and affiliations

Science  18 Mar 2011:
Vol. 331, Issue 6023, pp. 1366
DOI: 10.1126/science.331.6023.1366-d

Socially complex species such as humans, elephants, wolves, and orcas establish strong bonds among individuals that persist after periods of separation. These “fission-fusion” dynamics require an ability to recognize individuals even after periods of absence. Such long-term individual recognition has often been attributed to large-brained species with strong sociocognitive abilities; however, bats also display this ability. Whether these dynamics involve individual recognition or are purely driven by behavioral aggregation, however, is unknown. Bechstein's bats (Myotis bechsteinii) form stable colonies of females from April through September, which disintegrate during winter. Kerth et al. followed the movements of individually marked Bechstein's bats in two well-studied populations over 5 years. Analysis of 20,500 roosting sites revealed that individuals show consistent preference for individual roosting partners, who may differ in age, morphology, and family, and that these preferences persist over years, even after separation. These communities resemble those found in other socially complex species, which suggests that although social complexity is demanding sociocognitively, it may not require a large brain.

Proc. R. Soc. London Ser. 278, 10.1098/rspb.2010.2718 (2011).

Navigate This Article