Behavior +/- Genes
All living creatures are open systems: i.
e. all atoms we are made of keep changing, some rapid/some slow. Thus if we eat & store less than loose daily, wt. will go down; more & wt will go up. Storing additional matter in times of feast vs. famine ?es odds survival in times of famine, thus a genetic advantage. But key is behavior/intake & cannot become obese without storing more than loose daily.