"Our Babies Ourselves: How Biology and Culture Shape the Way We Parent" by Meredith Small is a great book which compares the more natural, instinctive child-rearing practices of hunter-gatherer cultures against the unnatural, anti-instinct techniques (cribs, bottles, "cry-it-out") that tend to be used in some (not all) Western, industrial cultures. Tribes with hunter-gatherer histories in S. America, Africa, etc. are specifically referenced.
Read the reviews at Amazon.com here:
http://www.amazon.com/exec/obidos/tg/detail/-/0385483627/qid=1066155226/sr=1-1/ref=sr_1_1/102-4867913-6080954?v=glance&s=books#product-details