Matt Ridley

causes of, 263—65

among primates, 213—15

and gender differences in, mentality,

sex-selective, 122, 126, 197

250

Infidelity, set Adultery

gene for, 279—80

1nheritance, patterns of, 197—98, 238—43

pornography and, 270, 271

Insertions, 85

Hormones

Instability, 83—84

brains and, 254—58

Instinct, 313—16, 322—23

fat distribution and, 292

Intelligence, 276, 309—44

homosexuality and, 264—65

artificial, 320—21

sex ratio and, 123—24

brain size and, 3I0—12

sexual selection and, 156—57

communication and, 332—34

Hrdy, Sarah Blaffer, I25—27, 2I2—13, 215, competition and, 33 — 34

231

learning and, 313—16, 321—23

Hudson, Liam, 253

Machiavellian theory of, 3 33—37

Hume, David, 21, 349

nurture and nature and, 316

Hummingbirds, 39

sexual selection and, 338—44

Humphrey, Nicholas, 33, 330—33, 336—37

socioecological explanation of, 192

Hunter-gatherers, 188—91, I93—94,

toolmaking and, 323—26

211—12,

228—29,

227,

244

youth and, 342—43

accumulated knowledge of, 325—26

Intragenomic conflict, 92

sexual division of labor among, 250, 251, In-vitro fertilization, 121

259, 262

Irons, William, 244

Hurst, Lawrence, 97, 102—3, 109, 280

Huxley, Julian, 35, 135, 136, 164

Jacot, Bernadine, 253

Huxley, Thomas Henry, 53