Animals that co-operate with non-relatives represent a challenge to inclusive fitness theory, unless co-operative behavior is shown to provide direct fitness benefits. Inheritance of breeding resource
Previous studies have suggested that deafness could lead to deficits in motor skills and other body-related abilities. However, the literature regarding motor skills in deaf adults is scarce and exist
Kin selection theory is foundational in helping to explain the evolution of sociality; however, the degree to which indirect fitness benefits may underlie helping behavior in species of early stage so
The data are part of the Jyväskylä Longitudinal Study of Personality and Social Development (JYLS), in which the same individuals have been followed over 40 years. This research stage includes a Life