Sociobiology

Sociobiology:

Learning objectives: 

  1. Define sociobiology

  2. Raise examples from some important social behaviors

  3. Explain nature and nurture

  4. 3 basic tenets of human sociobiology research

  5. Criticisms of basic tenets


What is (human) Sociobiology?

  • Scientific study of the factors driving the evolution of social behavior.

  • Example: adaptive evolved physical trait, thick fur for animals living in colder regions

  • Example: adaptive evolved social behavior, mothers protective of offspring, altruism, aggression (behavior can evolve)

Dmitri Belyaev’s Fox Breeding Experiment: Belyaev selectively bred silver foxes for tameness (friendly, non-aggressive behavior toward humans). Over generations, the foxes became much more tame and also developed physical changes such as floppy ears, curled tails, spotted coats, and more juvenile, playful behavior. This demonstrated that behavior can evolve genetically, and selecting for a behavioral trait can produce broad physical and behavioral changes. It supports the idea that social behavior has a genetic basis and can be shaped by evolution.


History of Sociobiology: 

  • Charles Darwin was the first person to think about human behavior evolving

  • Basic facial expressions are human universals (meaning that different cultures can recognize each others emotions)

  • Facial expressions may be functional (bitter/bad smells, disgust leads to avoidance of harmful material, and facial expressions communicate danger/safety)

  • E.O Wilson (sociobiology: the new synthesis 1975): argued that we should analyze social behaviors through evolutionary lens- animals behave in ways that maximize reproductive fitness


Evolutionary Psychology: new paradigm for psychological science (David Buss)

  • Focuses on psychological processes- attempts to identify evolved, underlying psychological mechanisms that influence behavior.

  • Humans have emotional, motivational, and cognitive adaptations that generally increased fitness in the past


Important to consider:

  • Some evolved behaviors may currently be maladaptive. Environments change!

  • Ex: motivation for high sugar/high fat foods may have helped our ancestors finding high quality foods and survive (causes health issues when food is abundant)

  • Because some behavior is “natural”, in the sense that it evolved and has a genetic basis, does not say anything about whether it is “morally right”


Nature interacts with Nurture:

  • Social and cultural factors change human behavior but biological factors also play a significant role.

  • Humans have the capacity (likely an evolved one) to regulate behavior in socially acceptable ways (Phineas Gage socially inappropriate behavior after frontal lobe damage supports the idea)

  • “Nurture” (environment) can flexibly regulate gene expression.

Basic Tenants of human sociobiology research:

  1. The human mind and human behavior are/were shaped by natural selection

  • (anatomically and behaviorally)

  • The cinderella effect: evolution favors ensuring survival and reproduction of genetically related offspring (inclusive fitness: evolutionary success comes not just from your own reproduction but also the reproduction of relatives who share your genes and that's what the cinderella effect is based on)

The phenomenon of favoritism for genetically related children and higher incidence of mistreatment by stepparents than by biological parents.

  1. The human mind uses heuristics (strategies) to increase the likelihood of solving problems our ancestors routinely faced.

  • Cheater detection (Watson task): a puzzle posed in an asocial context is difficult to solve. When the same puzzle is worded in a social manner ( that is evolutionary relevant), the puzzle is a lot easier.

(you are given 4 cards, each has a # on it, if a card is red on one side, it has a 3 on the other side)

Watson summary: tasks were logically identical, but one seemed easier to complete than the other

  1. There is a shared, and more or less universal, core human nature

  • Mate age preference by sex

(consistent across different cultures– suggests a common evolved human trait

- facial symmetry is attractive (more symmetric faces are more attractive)


Controversies and criticisms:

  • Naturalistic fallacy: not all of our traits/behaviors are good

  • Biological determination- we are influenced by society, not just by genes

  • “Just so” stories (unverifiable narrative explanation)- we should not use stories when we don't have sufficient evidence

  • Little is known about humans in ancient times.