 | This article needs more reliable medical references for verification or relies too heavily on primary sources. (June 2014) |  |
| Part of a series on |
| Sex differences in humans |
|---|
 |
| Biology |
| Medicine and health |
| Neuroscience and psychology |
| Sociology |
Sex differences in humans have been studied in a variety of fields. Sex determination generally occurs by the presence or absence of a Y chromosome in the 23rd pair of chromosomes in the human genome. Phenotypic sex refers to an individual's sex as determined by their internal and external genitalia and expression of secondary sex characteristics.[1]
Sex differences generally refer to traits that are sexually dimorphic. A subset of such differences is hypothesized to be the product of the evolutionary process of sexual selection.[2][3]
- ^ Purves D, Augustine GJ, Fitzpatrick D. "What is Sex?". Neuroscience (2nd ed.). Sinauer Associates. Retrieved 2019-05-09.
- ^ Mealey, L. (2000). Sex differences. NY: Academic Press.[ISBN missing]
- ^ Geary, D. C. (2009) Male, Female: The Evolution of Human Sex Differences. Washington, D.C.: American Psychological Association[ISBN missing]