Evolutionary Psychology #1
I am currently reading a fascinating book, named ‘Evolutionary Psychology- David M.Buss’. In this series, I will be documenting my notes and research as part of the learning process.
Sexual Selection
Darwin had a wonderful scientific habit of noticing facts that seemed inconsistent with his theories. He observed several that seemed to contradict his theory of contradictions. — page 6
Perhaps the most famous example is the feathers of a Peacock. As magnificent as they are, there is simply nothing about them that would aid this peacock in survival. This annoyed Darwin so much that it made him feel sick. He then developed a theory of sexual selection. In this theory he considers what might give animals a mating advantage. The traits that act negatively towards mating simply don’t get passed on, and so evolution is just as much about sex appeal as it is about survival.
Imprinting
Ducklings imprint on the first moving object they observe in life. usually this object is the duck’s mother — page 12
Ducklings/goslings have a critical period, 13–16 hours after hatching. In this time they will blindly follow the first moving entity they see. Years of evolution has given these animals this instinctual behaviour. All the children that don’t carry this instinct are less likely to follow their mothers during infancy. They naturally get left behind and don’t pass on the undesirable trait. Konrad Lorenz, a founder of ethology (study of animal behaviour) did some interesting experiments regarding imprinting.
He had another experiment where he made them follow a box on a train set, going in circles. This made me realise that there are way worse things for a baby duck to follow than a human being.
Inclusive fitness theory
This term was coined by a young graduate in the 60’s, called William D. Hamilton. The definition of fitness at that point was all to do with the animal’s ability to survive and pass on their own DNA. However, Hamilton outlines that animals will also help their relatives to survive and reproduce. If an animal helps its sibling to survive and reproduce, it is still facilitating the passing on 50% of its DNA, albeit indirectly. This can benefit the species as a whole and has become an evolutionary feature as a result. Humans seem to demonstrate a lot of examples of inclusive fitness theory.
The Garcia Effect
It’s the 1950’s, American psychologist John Garcia is chilling in his lab, exposing some rats to radiation. All of a sudden he realises; the ill rats aren’t drinking from the water bottles. He suspected that the rats were associating the taste of the plastic with the sickness that came from radiation. Pursuing this curiosity, he gave the rats some food, then after a couple of hours gave them radiation poisoning again. What he found was that the rats would associate that food with sickness and avoid it in the future. This shows that we have picked up taste aversion as an evolutionary defence mechanism, not one that requires teaching.
Thank you for reading