Human reproductive behaviour and sexual selection. Flashcards
Nature of sexual selection?
Comes from Darwin and it is essentially ‘survival of the fittest’ but ‘survival of the sexiest’ is also linked in.
It gives the idea that any trait that is passed on into an offspring increases chances of survival and reproductive success.
It looks and INTRA and INTER sexual selection.
INTRA sexual selection.
This refers to mate competition and it is when two member of the same sex compete against each other for a member of the same sex.
The victor gets to pass on their genes and whatever trait which influenced the victory gets passed down onto the offspring.
This increases chances of future survival.
INTER sexual selection.
This refers to mate choice and revolves more around the females.
Females needs to be more choosy so their partner needs to have certain preferences.
The preferences reveal what the males must compete against to ensure reproductive success (e.g. height.)
Humans are thought to be ‘pre-programmed’ to display such indicators that females look for which can be facial expressions for example.
Long and short term mating.
This has came from the nature of sexual selection.
According to the parental investment theory, man have evolved a greater desire for casual sex when compared to females.
This is because males can produces more gametes (sperm) than females do eggs (gametes.)
If a women was to have sex loads of times they will only produce one child but if a male has sex loads of times they can have potentially unlimited offspring’s and their genes will be passed on.
Long term mating preferences has been thought to have evolved from females as they have high levels of choosiness.
But, it has been found that if members of the both sexes invest heavily into one offspring then they are both having high levels of choosiness.
If a long term relationship ends badly down the line it can be a negative consequence for both sexes as they have both wasted resources, BUT it is worst for women as they are biologically obliged to invest in their offspring.
This is where the high levels of choosiness comes from.
Evaluation - Buss?
Provided support for the universal sex differences in long term mating preferences.
He explored what males and females look for in a partner.
He did this by doing a survey on 1,500 people in 37 cultures.
Found that women looked for men with ‘good financial prospects’ which can translates to men with good amount of resources.
He also found that men looked for women with good and high physical attractiveness which can translate to high fertility and high reproductive value.
Universally, it was also found that males looked for younger women which indicates high fertility.
Both sexes looked for the trait intelligence which can link to good parenting skills, they also looked for kindness which can link to long term mating.
However - validity? Buss’ comeback?
However, Buss’ study have been found to lack validity as it is a survey looking at mate preferences rather than looking at the real world.
This can also lead to the study being deterministic.
However, Buss counterbalanced these claims by finding that similar results in the real world.
He confirmed that men intend to look for younger women after they have divorced which was found in a real life study conducted within 29 cultures.
Evaluation - Gender biased? Greiling and Buss.
It has been found that the theory is gender biased when it comes to short term mating.
It has been put forward that the trait couldn’t have evolved with the absence of females so the females must benefit from short term mating in some way as well.
Greiling and Buss suggested that women can benefit from short term mating for a number of reasons and some of those reasons were a break up from a long term relationship or the chance to produce genetically diverse children.
The advantageous view for males give it a biased point of view as it does not show the advantages from the females perspective.
Evaluation - Penton-Voak et al and the menstrual cycle.
Looked at the menstrual cycle and how mate choice can vary with females.
Found that women choose males with a more feminised face for a long term relationship.
But, for a short term relationship and during the high risk phase of the menstrual cycle it was found that females seek males who have a more masculine face.
Feminine qualities link to traits such as kindness and cooperation with parental care.
Masculine qualities links to conception and high reproductive values.
