Editing Haidt 2012

== Haidt Ch. 9: Why Are We So Groupish? ==

=== Exhibit A: Major Transitions in Evolution ===
*Life on Earth underwent a “major transition” around 2 billion years ago
**Cells became more complex–developed internal organelles which worked together instead of competing
**Single-celled eukaryotes spread throughout the oceans
*A few hundred million years later: some eukaryotes develop ability to stay together after cell division and form multicellular organisms
**Also suppresses competition because each cell only reproduces if the organism as a whole reproduces
*Whenever a way to suppress free-riding emerges, natural selection at the higher level wins out over selection at the lower level
**Favors most cohesive “superorganisms”
*Fittest groups pass on their traits
**Genes created selfless group members which constituted a selfish group
*Groups used new forms of technological innovation
*Some groups are ultrasocial: live in very large groups with internal structure around division of labor
**One key feature: need to defend a shared nest
**Two other features: need to feed offspring and intergroup conflict
**These three factors applied to humans
*Group selection leads to group related adaptations

=== Exhibit B: Shared Intentionality ===
*Chimpanzees rarely work together
*In an experiment conducted on chimps and human toddlers, both did equally well on assigned tasks, but chimps failed social challenges whereas children aced them
*Humans developed shared intentionality: work together to overcome challenges or towards a common goal
**Increased early humans’ ability to hunt, gather, raise children, and raid others
*Tomasello: human ultrasociality arose in two steps
##Ability to share intentions in groups of 2-3
##Natural selection favored group-mindedness: shared social norms, beliefs, institutions, goals, etc. 
**Created selection pressures within groups
*Humans’ “shared defensible nest” is our moral communities

=== Exhibit C: Genes and Cultures Coevolve ===
*Only around 600,000-700,000 years ago where hominids began to cross over into shared intentionality
**Most likely Homo heidelbergensis that made this cross
*Richerson and Boyd argue that cultural innovations evolve similarly to biological ones; you can’t study one without studying the other
**Thus, cultural innovations around morality might have led to genetic responses, ultimately leading to ultrasociality
*“Tribal instincts hypothesis”: human groups have always been competing with neighboring groups
**Groups with cultural innovations that allowed them to cohere better usually won
*Example: body modifications like tattoos and piercings might have started off as a way to establish a sense of community by creating a physical resemblance/commonality
*“Self-domestication”: groups selected those who conformed to social and group norms best
**Selected friends and partners based on “ability to live within the tribe’s moral matrix”
**Created friendlier, gentler humans and conditions for peaceful coexistence