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Natural Selection is the source of Humanity Evolutionary psychologists look at aspects of human behaviour and cognitive abilities and seek to establish how these characteristic traits have been passed down in an evolutionary sense. Using a multi-method approach, they present scientific facts to support their claims that all life forms that exist today are the result of ‘selective’ forces which promote subtle changes to the original structure of DNA over extremely long periods of time. The focus of this essay will attempt to explain what ‘selective forces’ are and how the natural selection theory can explain how certain behavioural traits are inherited. Charles Darwin, (1809-1882) originally wrote about the origin of species in an attempt to explain that every living thing had evolved from something else. He used his discovery of the variance within the finch species to support his theory (Clegg, 2007). His claims caused a lot of controversy (especially from those with religious beliefs), as it contracted the notion that all species were fixed at creation. A lot of criticisms of his theory were due to lack of understanding in the translation of what he actually meant. It has therefore taken the development in other disciplines (such as biology) with empirical evidence to prove what Darwin originally suggested many years ago is indeed true. Traceable genetic evidence has proven that we inherit our original set of genes from our parents and the reproduction process that all living organisms must go through, replicates billions of copies of the original gene pool until it becomes a fully developed individual (Toates, 2007). On the flip side to ‘not getting it’, many people did understand what Darwin was trying to say. One of these is the evolutionary biologist, Richard Dawkins and in 1976 he publicised a book called the ‘selfish gene’ theory (Clegg, 2007). He claimed that people act as ‘vehicles’ to contain the genes, and these are passed on when the reproduce (Clegg, 2007, p.121). This caused uproar from evolutionary critics, as it was interpreted that Dawkins was implying that human beings are selfish and that as individuals, we have no control over this fact. Critics claimed that this theory could not be true as humans display universal altruistic behaviour (helping others), so how could we be both ‘selfish’ yet ‘kind’' But this isn’t what he meant! He simply used the word selfish to describe genetic transmission, in that the genes contained within us only ‘care’ (and this is not implying that genes have emotions) about reproductive survival. He was trying to explain natural selection in a modern day example. To understand what is meant by natural selection, we need to explore the components of it. Darwin’s finch species example is a good place to start as it is an undeniable fact that selective forces determined the variations within that species (natural and sexual). To simplify; the original finch was at some point in evolution separated from others of it’s kind (possibly due to lack of resources within it’s current environment) and in order to aid future survival (reproduction), it interacted (sexual selection) with another type of land bird and the results, their offspring, was a variation of the two species. So, looking at how the reproductive system works, the offspring’s genes would have been made up of its parents’ genes, yet it would not be identical due to its unique DNA. Say for example the land bird that the finch mated with was better at gaining resources such as food (because it had a longer beak that could peck deeper into the ground to obtain insects), it would have a survival advantage when competing for food against those that did not have this characteristic. It is therefore likely that the gene that aided this would have been passed onto it’s offspring as it increased the chances of survival of the individual. It is also important to note that the same offspring would have also contained genes from it’s ‘less’ advantageous parent and this is where natural selection comes into play. Reproduction is all about the survival of genes being passed onto future generations, so a trait that decreases its chance of survival within its current environment will eventually be removed. This is how species’ develop and change over time which makes the evolutionary claim that human beings today evolved from something else, a very strong argument indeed. Natural selection is a two-pronged process as we cannot reproduce on our own, so we need to’ choose’ a mate. So if natural selection is basically a concept of ‘survival of the fittest’ (so to speak), then how do we determine which mate will be most likely to help us reproduce successfully' Darwin (1809-1859) used the peacock s tail as an excellent example of how sexual selection works (Clegg, 2007). A peacock that has inherited the genes that are able to resist parasite infestation displays a magnificent tail, this means it is externally advertising the fact that it has an advantageous chance of survival (the gene that codes parasite resistance) and is therefore a ‘high’ quality mate choice as it’s offspring are likely to inherit this trait. Although this is advantageous for reproductive success, it is also costly to the peacock as it is more visible to its predators and more likely to get eaten! Those that do not have this reproductive advantage could attempt to ‘cheat’ by replicating this characteristic, but this would be a short-term strategy as it would eventually be found out (it’s offspring would have the decreased chance of fighting infestation and therefore be unable to survive to a reproductive age). To conclude, it would seem that evolution is like a gigantic jigsaw puzzle that spans over millions of years and as it is not possible to travel back in time, evolutionists utilise archaeological (fossil evidence and artefacts) plus genetic data in order to gain empirical evidence to support their theories about how and why we appear as we do today. Fossil evidence such as fossil bones can provide information on the bodily structures of early humans, like their brain size, size differences amongst males and females and whether or not they walked on all fours or two legs (Clegg, 2007). Biology can help us understand how reproduction works and how the cycle of life began. By considering all of the scientific evidence available, we can indeed explain that altruism is seen as an adaptive trait of our ancestors as it appears to be universal across cultures and other animals. It may seem obvious why we behave altruistically towards our kin (genetic relatives – siblings, cousins etc), as this will help us pass on copies of our genes. But what do we gain by behaving in such ways towards complete strangers' This is where the selfish gene theory makes a lot of commonsense. By helping others, it may originally seem a cost to oneself, but by helping others whether related in a ‘kin’ or ‘reciprocal’ way, we increase the chances that our species will continue on for generations to come. Word count: 1163 References: Clegg, H. (2007). Evolutionary psychology. In D. Meill, A Phoenix & K. Thomas (Eds.), Mapping Psychology (2nd ed., pp.105-165). Milton Keynes: the Open University. Toates, F. (2007). Biological processes and psychological explanation. In D. Meill, A Phoenix & K. Thomas (Eds.), Mapping Psychology (2nd ed., pp.235-248). Milton Keynes: the Open University. Part II Methods Q1, (a) The variables shown are the independent variable – Hours spent practising and the dependent variable – Exam mark. Q1, (b), (iii) ‘neither’. Q1, (c), iii) ‘medium’. Q1, (d), (v) ‘amount of practise is a moderately good predictor of exam mark. Q1, (e) Variable 1 = Time spent practising and Variable 2 = Musical ability. Q1, (f) Yes it is a valid conclusion that there is a stronger association. Q1, (g) Without performing a statistical test to determine the exact effect the removal of the data would have on the correlation coefficient, a common sense approach has been employed. Had pupil 3’s data not been removed, then it would weaken the association as the low exam mark was more likely to be due to the pupil being poorly on the day of the exam . Therefore, the removal of this pupils data would strengthen the correlation coefficient. Q2, (a), (ii) ‘whether or not the stooges were present’. Q2, (b), (iv) ‘the accuracy of the participant on critical trials’. Q2, (c), iv) ‘between participants because some worked with stooges and some did not’. Q2, (d), (ii) ‘the time for which the original target picture was shown’ and (iv) ‘the order in which 30 sets of pictures were shown’. Q2, (e), (ii) ‘time of day of session’, (iii) ‘the gender of the participants’ and (v) ‘the length of the experiment’. Q2, (f) It is important to have both critical and non-critical trials in the experiment to control as many confounding variables as possible, that may effect the results. Some of these could be ‘demand characteristics’, ‘order effects’ or ‘habituation’. Q2, (g) There were only 5 pictures shown in each sequence so the chance probability would be 20%. This means that it is not a valid criticism as 50% (the baseline results from the pilot study) is higher than 20% (the chance probability result). Q2, (h), (ii) ‘quasi-experiment’. Q3 A hypothetical quasi-experiment designed to test if lying detection abilities are superior when the person lying is from the same cultural group. The aim of the above experiment is to test if the above hypothesis is true, false or neutral and as it requires participant selection based on existing characteristics, in this case ‘cultural group’, it will be a quasi-experiment employing a within-participants design. For the purpose of this experiment, I shall recruit a sample of Cretans and Mainland Greeks by putting an advert in their relative local newspapers. I shall recruit 60 mixed-gendered participants from the two different cultures and split them into their relevant cultural groups. The participants will then be taken individually to the ‘lab’ and asked to watch a video on their own. The video (the stimuli) they will all watch will contain 2 actors (the independent variable),one Cretan and the other a mainland Greek being asked a series of questions. The actors will answer truthfully to some questions and lie in the others. I shall recruit an independent camera-man to film the video and ask him to record which are truths/lies, but withhold this information from the experimenter until every participant has watched the video. This will employ double-blind testing to avoid experimenter effects. All participants will be asked to watch the same video containing both actors (within- participant design) and instructed to signal if they think the actors they are watching are telling the truth or lying. Once the experiment has been conducted, I will debrief the participants and explain what the experiment was testing for. If all participants are happy for me to use their data (the dependent variable), I shall compare the results from each group in order to accept or reject my hypothesis. 293 words References: DSE212 Course team. (2007). Exploring Psychological Research Methods, (pp. 54-76). Milton Keynes: the Open University.