Date of Award




Document Type

Master's Thesis

Degree Name

Master of Arts (MA)


Department of Psychology


Behavioral Neuroscience

Content Description

1 online resource (vi, 75 pages) : illustrations (some color)

Dissertation/Thesis Chair

Gordon G Gallup

Committee Members

Bruce Svare


hand grip strength, indigenous population, phenotypic fitness, reproductive success, wrist width, Grip strength, Wrist, Sexual selection, Sex differences

Subject Categories

Biological and Physical Anthropology | Biological Psychology | Psychology


Correlating a sexually dimorphic trait with reproductive success (RS) remains the `gold standard' in evolutionary psychology research. Within each sex, if more dimorphic individuals have increased RS then this is strong evidence that the trait is an important phenotypic fitness marker and potentially used as a same-sex and/or mate-assessment criterion. Many studies have investigated some of these traits, like shoulder to hip ratio (SHR) in males and waist to hip ratio (WHR) in females and have found that a more sex-typical body configuration does indeed indicate higher phenotypic quality and is used in mate assessment. However these traits are aggregate measures of soft tissue and skeletal features. As a result they are highly susceptible to the effects of senescence as well as to short-term fluctuations in weight and/or the general health of the individual. Thus they may not capture an accurate assessment of the degree of sexual dimorphism in the individual at the time of measurement, particularly among the elderly, Western populations who have access to unlimited calories and ample leisure time or individuals who can only be assessed for short periods of time such as those living in traditional societies. Due to these limitations a novel assay of the degree of sexual dimorphism of an individual would be of great scientific merit.