The essay on a whole is a bit long, but in an exam it would be difficult to remember everything anyway, this essay got me 25/25
Discuss the evolutionary explanation of food preferences (25 marks) 9+16
Evolutionary psychologists argue that all behaviour can be analysed and understood as having been adaptive and functional in some way in the past. The goal of any evolutionary psychologist is to discover the adaptive function of a particular behaviour, thus we need to consider the problems faced by our distant hunter-gatherer ancestors to discover why the food preferences that people have today evolved in the first place.
One problem that our ancestors faced was food shortages. Food was not as plentiful as it is nowadays so our surviving ancestors would have been those who ate high calorie foods as this would have been retained for future periods of food scarcity. This problem has been argued to have created our preference for innutritious foods which are rich in calories such as McDonalds. However, as nowadays people have less need for these high calorie foods due to the vast food availability, we still seem to retain this preference.
Babies’ innate preference for sweet foods can also be explained in evolutionary terms. The preference for sweet flavours would encourage babies to eat fruit with natural fructose. As this is high in calories, it would provide the baby with the much needed energy. Evidence for this preference comes from Desor et al (1973), who using facial expressions and sucking behaviour as an index of preference, found that babies prefer sweet tasting substances.
Furthermore, people tend to enjoy consuming salty flavours. Although this is less easy to explain due to the human body having little need for additional salt, as it is difficult to obtain in the wild this flavour may have encouraged people to eat meat. Beauchamp (1987) found that at the age of 2 years, children reject foods that to not contain the expected amount of saltiness, showing how humans do possess an innate preference for salt.
The additional preference for the preference of meat is that it is full of nutrients and provides the catalyst for the growth of the brain. Milton (2008) proposed that it is unlikely that early humans could have secured enough nutrients from a vegetarian diet to evolve into the active and intelligent creatures that they have become today from a vegetarian diet.
Finally, the general dislike for bitter foods and food neophobia can be explained because avoiding they would have helped to protect people from eating food that was poisonous, and it would be useful for children who would then not try and eat wild berries that could be dangerous.
However, the evolutionary explanation to food preferences had been criticised both positively and negatively. Firstly, in support of the approach, it can explain why people have a love for chocolate and fast foods even thought they are not required nor healthy. This could explain why obesity levels have risen so rapidly in the last 50 years. There is a greater availability of food, yet our preferences are still of the time when food was a much more limited selection.
Birch and Marlin (1992) offer support for the belief that children are neophobic. Researchers exposed two year olds to new foods for a period of six weeks and in this period the infants showed an increased preference for that food. A minimum of 8-10 weeks was needed in order to reverse the nephobia into a preference.
However, the evolutionary explanation to food preference is very deterministic. From the explanation we are told that our preferences are pre-determined, we just inherit those that were useful for the survival of our ancestors. Yet, this does not seem to always be the case. Should we not be able to exert any free will over our food preferences, then it does not make sense that humans on a whole can for example decide to eat a healthy balanced diet, whereas others refuse to eat anything but junk food. This leads us to believe that the evolutionary explanation is reductionist because it reduces the many social and complex factors which influence our preferences for certain foods into simply, the benefits that certain food preferences would have had for our ancestors hundreds of thousands of years ago. It ignores other factors such as the culture we are brought up in, or family and other social pressures. For example, children who grow up in India usually prefer spicy foods in comparison to those from Japan who may prefer fish based dishes. This supports the behaviourist approach, that we can learn to like foods because of our upbringing (nurture), not just that our preferences are programmed within us from birth (nature) as the evolutionary explanation suggests.
Another problem with the evolutionary explanation is that it is difficult to falsify, thus not a scientific explanation. Although the concept of adaptation can be applied to many behaviours, for example, eating, forming relationships, aggression it is difficult to demonstrate empirically. This means that we cannot be sure that evolution was the cause of human’s current preferences because although there is evidence from fossils showing that humans would have had a particularly meaty diet, scientific research is limited as our ancestors have now died out. However, a common way of testing an evolutionary hypothesis is through comparison with a different species e.g. chimpanzees who face similar adaptive problems today. Yet, the fact that humans and animals are different, there are problems regarding how accurate this explanation of food preferences can be generalised to humans.
Overall, it seems that there are many good arguments put forward by evolutionary psychologists in an attempt to explain modern-day food preferences, by those problems which our hunter-gatherer ancestors faced. However, it does seem likely that our preferences may have been shaped by a number of factors, not just evolution alone.