The Rational Animal by Douglas T, Kenrick and Vladas Griskevicius

The Rational Animal: How Evolution Made Us Smarter Than We Think by Douglas T. Kenrick and Vladas Griskevicius (U of MN professor)  attempts to describe the underlying evolutionary behaviors that explain why behaviors that first appear irrational have solid reasons for being part of the human and animal responses to environmental stimuli. They authors refer to a wide range of studies and offer these up with tasteful goblet of dry wit served slightly chilled.

The authors suggest that humans do not possess a single character but consist of seven fragmented sub-selves that respond to priming.  The classic marshmallow experiment that predicts future success in life can be be altered easily.  If the person offering up the marshmallows demonstrates unreliable and untrustworthy behavior, the kids will choose to not wait for the next marshmallow.

People who grow up in stable environments will often adopt long term conservative delayed gratification strategies for accumulating and retaining wealth.  See rock star Gene Simmons' book Me INC .  Individuals growing up in unstable environments live fast and burnout quickly.  Many other rock stars, Jim Morrison, Janis Joplin, Jimi Hendrix and others don't even make it to age 30. M.C Hammer went quickly from rags to riches to back again in a very short period of time.

Mating behavior can be deadly and expensive if the male to female ratio is out of balance.  The authors point to a study of credit card balances in two Georgia counties.  In the county with many more males than females, men's credit card balances were significantly higher as they spent money attempting to woo females.  The risky showing off behavior results in male death rates at 5 times those of females in Spain for those in their 20's.

In a section on parasites, the authors explain how the advertising slogan, "A diamond is forever", now successfully extracts approximately 2 month's salary from the proposing fiance.  Prior to the early 30's there was no strong tradition of exchanging diamonds. The diamond company has also penetrated the Japanese market where the exchange of diamonds had previously not been part of the wedding ritual.  

Rational Animal - 3.5 minutes

Why Do We Put Diamonds on Engagement Rings -Brain Stuff -  2.5 min.