Nature or Nurture?
How much of behavior is pre-determined genetically or imprinted by environment (abiotic and/or social)?
Identical twins, genetically identical but separated after birth: many similarities in personality, temperament, interests suggest at least some genetic influence
Robert Tyron’s “smart rats” (1940s): inbreeding of “smart” rats increased “smart behavior”
Hybrids often intermediate behavior
“Bad mother rats” (1996): fosB gene needed for development of maternal care in rats