Transgender hormone therapy (female-to-male) to individuals taking bioidentical hormones in the form of testosterone (including esters) and do not apply to those taking synthetic AAS (e.g., nandrolone) or dihydrotestosterone. Transgender hormone therapy (female-to-male) Transgender hormone therapy of the female-to-male (FTM) type, also known as masculinizing hormone therapy, is a form of hormone therapy and sex reassignment therapy which is used to change the secondary sexual characteristics of transgender people from feminine (or androgynous) to masculine. It is one of two types of transgender hormone therapy (the other being male-to-female), and is predominantly used to treat transgender men and other transmasculine individuals. Some intersex people
Sexual selection in mammals neck length is not correlated to increases in other parts of the body, which would be expected from foraging selection, so sexual selection may be a more satisfactory explanation. Studies have failed to resolve the causes involved: perhaps the neck was a result of both or other forces. Precopulatory mechanisms determine who father an offspring prior to sex. Male-male competition is the biggest precopulatory mechanism in mammals. Sexual dimorphism is a result of male-male competition that is easily seen in species. Male-male competition to copulate with the opposite sex is often seen in mammals. African elephants strongly promote male-male competition.