Hormones also affect how we develop. For example, testosterone is needed to produce male features like muscle strength, body and facial hair, and a deeper voice. Testosterone can also lead to more aggressive, irritable behaviour. Dabbs et al (1995) – measured testosterone in saliva of 692 adult male prisoners. Found higher levels in rapist and violent offenders than in burglars and thieves. The same effects of testosterone were also found in women therefore demonstrating that hormones are a major factor in determining aggressive behaviour.
