Evolutionary Psychology (1) What is Evolutionary Psychology?
1) What is Evolutionary Psychology?
- Evolutionary psychology is an approach to asking and answering questions about how the mind works, in which basic principles of evolutionary biology are used to inform research on human psychology.
- Evolutionary Psychology is a combination of two sciences- Evolutionary Biology and Cognitive Sciences
-The study of the psychological adaptations of humans to the changing physical and social environment, especially of changes in brain structure, cognitive mechanisms,and behavioral differences among individuals.
- Genes that define human development are products of a long history of evolution by natural selection.
- The human nervous system typically develops according to a recipe encoded in those genes.
Evolution is simply change over long periods of time.
- Natural selection is the driving force behind this change
- The process of natural selection can be understood by these three components: variability, inheritance and differential survival
Variability refers to the fact that within any population of sexually reproducing organisms, individuals differ in many ways, such as color, size, shape, behavior, and other traits that may or may not be easily perceived.
- These variations provide the ‘raw materials’ for evolution, as there would be nothing for natural selection to select if organisms did not vary.
The gene has taken center stage in evolutionary theory, as it is the fundamental unit of selection.
Natural selection has no goals, foresight, or morality; all that matters are the effects that inherited traits have on survival and reproduction.
- The theorists in this theory are:
- David Buss
- Martin Daly
- Margo Wilson
- Leda Cosmides
- John Tooby
For example, different birds known as finches on the islands had different shaped beaks. The finches that ate nuts had beaks that were thicker and bigger for grinding nuts while the finches that had thin, small beaks that came to a point ate insects that they had to pull out from knotholes in trees.
- 4) History of Evolutionary Psychology
Charles Darwin is credited with the theory of evolution, which is the basis for evolutionary psychology. He spent time in the Galápagos Islands and noticed that the animals on each island looked different.
These finches' beaks changed physically through many generations of exposure to a particular food source, and as a result, the finches with the best beaks for that particular type of food were the ones to live long enough to reproduce, which fine-tuned the beaks to become specialized for one food source. This process of gradual change to produce organisms better adapted to the environment is known as natural selection.
Just as physical changes are produced to aid survival and reproduction, changes in human psychology (thoughts, preferences, and behavior) are produced to aid in survival and reproduction through natural selection.
- The study of these psychological mechanisms that developed to enhance survival and and reproduction is Evolutionary Psychology.
8)Six Core Principals:
-The human brain's purpose is to process information, and in doing so, it produces responses to both external and internal stimuli.
-The human brain adapted and has undergone both natural and sexual selection.
-The parts of the human brain are specialized to solve problems that occurred over evolutionary time.
- Modern humans have brains that evolved after problems recurred repeatedly over long periods of time.
Most of the human brain's functions are done unconsciously. Even problems that seem easy to solve require very intricate neural responses at an unconscious level.
-Many very specialized mechanisms make up the whole of human psychology. All of these mechanisms together create human nature.
2) Natural selection eventually leads to adaptation
defined as: defined as ‘an inherited and reliably developing characteristic that came into existence through natural selection because it helped to solve a problem of survival or reproduction during the period of its evolution
- Evolution may also result in by-products or noise By-products are characteristics that result from the existence of adaptations. A good example is the belly button, which has no adaptive function but results from the existence of the umbilical cord, an adaptation for obtaining nutrients throughout fetal development.
In short, for a particular trait to be considered an adaptation, it should exhibit reliability (reliably developing in all or most members of a species when in a species-typical environment), efficiency (solving the adaptive problem well), and economy (solving the adaptive problem without imposing large costs on the organism).Although these criteria are not exhaustive, attention to these criteria can reduce the possibility of mistakenly categorizing by-products or noise as adaptations.
3)Middle level Theories
- The theory of evolution by natural selection is simple: organisms gradually change over many generations as a result of inherited variants impacting survival and reproduction. However, evolutionary theory becomes more complex when one considers middle-level theories, which provide key insights that are consistent with, but not directly derivable from, general evolutionary theory.
- a process that emphasized the importance of reproductive success in determining the selection of inherited traits.
- Sexual selection further expands upon general evolutionary theory by describing two general contexts in which selection occurs. Example of intersexual selection, which refers to the selection of traits in one sex as a result of preferential mate choices by the other sex. The second context in which sexual selection operates is intrasexual competition, which refers to the selection of traits in one sex that provide a benefit in competing with same-sex rivals for access to mates. An example of intrasexual competition is two stags locking horns in combat. In competitions such as these, the victor gains increased mating access to members of the other sex.
Parental Investment Theory The theory of parental investment describes the important role that investment in offspring plays in determining sex differences in intersexual selection and intrasexual competition. Parental investment theory predicts that the sex which invests more heavily in offspring will also be more discriminating when choosing mates. Therefore, the sex that invests less in offspring is predicted to be more competitive and to engage in riskier behaviors in the pursuit of mating opportunities.
6) The Environment of Evolutionary Adaptedness:
- Another important concept within evolutionary psychology is the environment of evolutionary adaptedness (EEA), which ‘refers to the statistical composite of selection pressures that occurred during an adaptation’s period of evolution responsible for producing the adaptation.
- For every adaptation, there is a unique EEA, a unique set of selection pressures that played a role in the process of selecting for inherited variants that led to the construction of the adaptation in question.
7) Key Takeaways of Evolutionary Psychology:
- The field of evolutionary psychology is based on the idea that human emotions and behaviors have been shaped by natural selection.
- According to evolutionary psychologists, the human brain evolved in response to specific problems that early humans faced.
-A core idea of evolutionary psychology is that the behavior of humans today can be better understood by thinking about the context in which early humans evolved.