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Outline and evaluate the evolutionary explanation of parental investment (24 marks)

Outline and evaluate the evolutionary explanation of Parental Investment (24 Marks):

Trivers defines parental investment as any investment made by the parent in an individual offspring that increases the offspring’s chance of surviving at the cost of the parent’s ability to invest in other offspring.

Female investment tends to be far greater because female gametes (eggs) are limited and more costly to produce than male gametes (sperm). They also invest more because they carry the baby for 9 months and breastfeed the baby after it’s born. Also, a mother can always be positive that the baby is hers whilst a father can never be too sure thus they invest less. The great vulnerability for men is that they invest too many resources in a child that may not be there’s. For a man, an unfaithful mate meant that he risked investing in offspring that were not his own. This is known as cuckoldry. For women, an unfaithful mate may have led to the diversion of resources away from her and her family. Buss suggested that sexual jealousy might have evolved as a solution to these problems. Men may be more jealous of their mate engaging in sexual contact with other males whilst women are more jealous in the shift of emotional focus. Women are also generally choosier in the selection of partners because they have more to lose from the negative match. A female’s best strategy is to select a resourceful, fit male to increase the survival of offspring. As a result, it will lead the offspring to spread their genes so that they are passed on to the next generation.

Buss (1995) suggested that sexual jealousy is higher in males than females. This is related to the fact that for males it is a priority to have faithful women in order to avoid investing in offspring that isn’t theirs. His study in 1992 supports this as males showed a higher galvanic skin response when asked to imagine sexual infidelity by their partner, than females. However, Harris found that males have greater arousal from any sexual imagery whether it’s relevant to them or not. She suggests that sex differences in jealousy are more likely to be a product from social learning than evolutionary hard wiring. Daly and Wilson explain that males devote most of their time and effort in courtship to ensure high levels of reproduction; this can explain why less time remains for investment. However, a limitation of this study is that results have been found using animals and may not be generalizable to humans as we are different mechanism thus act differently. Therefore this decreases the reliability of the evolutionary explanation for parental investment.

However, in reality fathers do invest in their children and do help out. Increasing brain size over the years has led babies to be born prematurely thus more investment by both parents is needed in order for the offspring to survive. According to the parental investment theory, males are more likely to care for their biological children than non-biological. However, Anderson et al (1999) suggest that this is an oversimplification as he found that males treated their step-children and biological children who were living with them similarly. This in itself can be explained by the evolutionary theory as males care for their step-children in order to gain greater access to their mother.

To verify if the lack of commitment was due to nature or nurture, Geher asked 91 students from New York University to complete a parental investment perception scale to measure how they see themselves as parents in the future. There were no difference between males and females. This suggests that men and women are socialised to invest in their offspring. However, when asked a question on actual parental investment level (e.g. would it be necessary to cancel work to look after your sick child?) males showed higher levels of ANS arousal. This may provide evidence that biologically men’s actual level of parental investment is lower than perceived thus supporting the evolutionary theory of parental investment. However, the results may contain social desirability bias as men may have felt obliged to say they would invest equally in order to seem socially acceptable. In evolutionary terms, this can be explained as men needed to say this in order to seem desirable to potential mates.

Overall, the evolutionary theory is reductionist as it reduces complex ideas into simplistic terms. It ignores all other factors that may influence whether parents invest in their child or not such as cultural factors. In some cultures men and women are both expected to invest in their child equally (Sweden). Rowe (2002) supports the argument that an explanation of parental investment based on evolutionary factors alone is limited. Men’s parental behaviour depends on various social and personal conditions such as the relationship with the mother and personality characteristics. It also ignores emotion as humans are generally caring and loving thus both parents will invest equally in their child.

The evolutionary theory is also determinist as it ignores our free will. We use our free will daily to influence the decisions we make. Men may decide to invest heavily in their child thus contradicting the evolutionary theory. We aren’t machines and don’t follow the rules all the time, and will certainly use our free will and as a result go against the evolutionary model of parental investment. Therefore, this decreases the applicability of the evolutionary theory in real life.

19/24 Grade A AQA A

Reply 1

TSR Jessica

Sorry you've not had any responses about this. :frown:

Are you sure you’ve posted in the right place? Posting in the specific Study Help forum should help get responses. :redface:

I'm going to quote in Puddles the Monkey now so she can move your thread to the right place if it's needed. :h:

Spoiler

Reply 2

Grace613

This is brilliant, really helpful, thank you so much!

Reply 3

_Sinnie_

Original post by sima28

Outline and evaluate the evolutionary explanation of Parental Investment (24 Marks):

Overall, the evolutionary theory is reductionist as it reduces complex ideas into simplistic terms. It ignores all other factors that may influence whether parents invest in their child or not such as cultural factors. In some cultures men and women are both expected to invest in their child equally (Sweden). Rowe (2002) supports the argument that an explanation of parental investment based on evolutionary factors alone is limited. Men’s parental behaviour depends on various social and personal conditions such as the relationship with the mother and personality characteristics. It also ignores emotion as humans are generally caring and loving thus both parents will invest equally in their child.

The evolutionary theory is also determinist as it ignores our free will. We use our free will daily to influence the decisions we make. Men may decide to invest heavily in their child thus contradicting the evolutionary theory. We aren’t machines and don’t follow the rules all the time, and will certainly use our free will and as a result go against the evolutionary model of parental investment. Therefore, this decreases the applicability of the evolutionary theory in real life.

19/24 Grade A AQA A

Hi there,

I don't want to sound like I'm trying to come along and bust your bubble, but I am curious about your conclusion. It's been a long time since I did A-level and it has changed a lot. Are these evaluative points taught as part of the curriculum or are you left to formulate your overall conclusions yourself? How in-depth do you discuss these models?

I'd consider factors like culture, interpersonal relationships, personality and free will to be either directly linked, or derived from evolution. I'd personally challenge the idea that evolutionary theory is reductionist or deterministic - at least in how it would be applied to real life scenarios. I feel that the picture of evolutionary theory you present is too narrow - but this may be what is asked of you in A-level?

Reply 4

lucywebb123

Original post by _Sinnie_

No conclusion is necessary for psychology, though it is obviously good to round off the essay, I have always been told conclusion is not necessary.
I think deterministic is a good IDA for evolutionary theories since they assume our actions (in this case parental investment) are determined by our ancestor's adaptive behaviours - which is simply not always the case - therefore they fail to account for human conscious thought and free will to make decisions in parental investment (as step-fathers do).
What do you mean by interpersonal relationships?

Reply 5

sima28

hi, when i was doing the psyc modules my teachers told me to set out my conclusion like this but things have probably changed even though i took these exams in 2015. by interpersonal relationships i mean relationships between two or more people based on trust, commitment etc. And also you can always expand the essay and add extra things that you feel neccessary as you can see this isn't a full mark essay