Are your feelings just another evolutionary adaptation? A discussion of the field of evolutionary psychology

Are your feelings just another evolutionary adaptation? A discussion of the field of evolutionary psychology

Psychology The study of behavior and mental function Goal is to understand behavior

Evolutionary Biology Studies how evolution has generated the diversity of living organisms

Evolution what is it? A change in a population over time

Evolution via natural selection

Peppered Moths (Biston betularia) Pre-Industrial Revolution Fittest

Industry established Dark Background Different selective pressure

Evolution via natural selection What we see are physical changes in a population Genetic changes really underlie that physical change Evolution = change in genetic make up of a population over time

Differential retention of alternatives Genetic differences are the source of variation in a population These are acted upon by the process of natural selection Natural selection selects either for or against a particular characteristic. Favorable characteristics increase in a population over time

Human Evolution Bipedalism (walking upright) Genetic change moved foramen magnum

Bipedalism Freed up hands for more efficient foraging Increased nutrients, improved reproductive success Characteristic passed on to next generation

So our physical characteristics are a result of evolution through natural selection Natural selection causes organisms to be adapted to a particular environment What about our emotions/feelings??

Evolutionary Psychology Field looks at whether our feelings/emotions are adaptations that increase our survival

Environment of Evolutionary Adaptation (EEA) Our behaviors are looked at in light of when they evolved Our Environment of Evolutionary Adaptation

Characteristics we have today are the result of selection that occurred in the past. Many of our behaviors or feelings may not necessarily make sense in relation to our modern lives.

Evolutionary Psychology Cooperation Kin Detection Mate Choice Infidelity Emotions as adaptations anger, jealousy, guilt

Romantic jealousy Jealousy Emotional state caused by a perceived threat to a valued intimate relationship

Question Imagine you discover that your partner formed a deep emotional and passionate sexual relationship with another person. Which aspect of your partner's involvement would make you more jealous? the deep emotional relationship? OR the passionate sexual relationship?

Emotional relationship Emotional jealousy Sexual relationship Physical jealousy

Why the difference Difference in the size of male and female reproductive cells (gametes) Sperm smaller and more numerous Eggs larger and less numerous

Creates different motivations Using reproductive cells entails a different amount of parental investment Females - lots of investment Males less

Females are choosy about a mate as a result Males are less choosy

Human Evidence

What are females looking for? Biggest and most colorful.. Humans?? Nice car, good job Indicate resource gathering skills Indication of males ability to provide resources to her and offspring Or just indication of genes that offspring will contain

Why are resources so important? Ultimate goal of an organism is to have offspring and aid in survival of offspring Passes genes into next generation Biological Fitness = # of offspring

So females are choosy in order to increases fitness Males don t necessarily have to be choosy to increase fitness

Back to jealousy Females are more likely to feel emotional jealousy because. Of potential redirection of resources Jealousy an adaptive feeling kind of like a warning alarm to indicate potential resource redirection

What about males? Strategy to be less choosy Gametes are made rapidly, low potential parental investment SO when in a monogamous relationship have physical jealousy

Cuckoldry Fear of cuckoldry Raising another males offspring Physical jealousy adaptation to reduce likelihood of cuckoldry

Evidence of cuckoldry in humans? Testes size in relation to body size Gibbons monogamous small Chimpanzees females have many partners large testes Humans somewhere in between

Adaptive because Emotional jealousy Potential Resource Redirection Physical jealousy Fear of Cuckoldry

Summary Human emotions (especially undesirable emotions) do appear to be adaptive They can be seen as warning lights of a potential decline in biological fitness

Further Resources Online Journal Evolutionary Psychology www.epjournal.net/ Center for Evolutionary Psychology UC Santa Barbara www.psych.ucsb.edu/research/cep/ David Buss - Research on jealousy Helen Fisher Research on romantic love and feelings associated with love

References Schützwohl, A. (2004) Which Infidelity Type Makes You More Jealous? Decision Strategies in a Forced-choice Between Sexual and Emotional Infidelity. Evolutionary Psychology. 2: 121-128 Source of question Buss, D & Schmitt, D. (1993) Sexual strategies theory: An evolutionary perspective on human mating. Psychological Review 100: 204-232 Source of graphs on male/female choosiness