BIOLOGICAL APPROACH- Evolutionary theories & Pheromones

Evolutionary theories

based on the assumption that behaviours are inherited.

Theories created so far

Natural selection, sexual selection, parental investment theory, intrasexual selection theory, etc.

Natural selection theory

For men, it is all about spreading their DNA, while for women it is about maximizing the potential for survival for their offspring

Clark & Hatfield (1989) Aim

Aim: see if there are gender differences in the approach to casual sexual activity.

Clark & Hatfield (1989) Procedure

Two experiments were conducted, one in 1978 and one in 1982. Same procedure.

Field experiment

a team of confederates, who ranged from mildly unattractive to moderately attractive, approached members of the opposite sex who were strangers. Asking them to go out on a date, or to sleep with them.

They were asked after every interaction to rate the attractiveness of naive participants. No significant difference was shown between the two gender groups.

The questions were asked randomly. Also only asked during weekdays, and not between classes or during rainy weather.

Clark & Hatfield (1989) Results

Both experiments show that 70% of the men were willing to have casual sex in both experiments. While none of the women agreed to do so.

Results also showed that the level of attractiveness of the confederate had no significant impact on the response of the participant.

Clark & Hatfield (1989) Implications

The study suggests that there may be differences in how men and women respond to casual sexual offers from strangers.

Relates to natural selection.

Pheromone

chemical messengers that are emitted into the environment from the body where they can activate specific physiological or behavioural responses in other individuals of the same species.

Androstadenione (AND) and Estratetranol (EST) role

influence the communication of gender information in a sex-specific manner.

AND biases humans to percieve others as more masculine

EST biases humans to percieve others as more feminine.

Zhou et al (2014) Aim

investigate if Androstadienone (AND) or Estatretanol (EST) influences human mating behaviour.

Zhou et al (2014) Procedure

sample of heterosexual men and women, and gay men and lesbian women was gathered

Laboratory experiment

Task for participants: watch stick figures walking on a screen and to determine their gender

While carrying out the task, they were exposed to 3 different smells of cloves: cloves mixed with andostadenione, cloves mixed with estatetranol, and a control condition where only cloves were used.

Zhou et al (2014) Results

findings showed that smelling AND biased heterosexual females and homosexual males, but not heterosexual males, toward perceiving the walkers as more masculine.

by contrast, smelling EST systematically biases heterosexual males and lesbian women toward perceiving the walkers as more feminine.

Zhou et al (2014) Implications

pheromones influence communication of gender information in a sex-specific manner.