Do we know if that picture is really accurate?

We do know, from skeletal fragments that have survived, that they were definitely smaller than present day human beings. We can surmise that they were wiry from the lifestyle they pursued: irregular availability of food and long hours of daily hunting. We can assume that women started to gather plants, grasses, fruits, and seeds to provide an alternate source of sustenance to the men's only intermittently successful hunting efforts.

We have only vague timelines on when tribes started to move out of caves and into shelters they made themselves. We can only guess about the invention of cooking pots, an enormous advance from simply an open fire.

As the race became more domesticated, the variety of food expanded and therefore the availability of something to eat became more assured. Eventually, civilization sparked, agriculture was born, and eating became a process of selection and choice rather than mere consumption to stay alive. It was at this juncture, we can posit, that individual's weights started to differentiate, depending upon personal choice, the wealth or strength to obtain extras, or the physical demands of one's occupation.

What did our cavemen forbears bequeath as their legacy?

Underfed and overactive, they willed us a body that still thinks we dwell in the primordial forest. Suddenly cut back on our intake of food and the alert is sounded through the nervous system and organs of our prehistoric physiology. "Famine coming, famine coming" our bodies shriek and immediately our metabolism slows to a crawl. The body attempts to hold onto its fat like a Paleolithic hunter grasping his animal skin against the elements.

In the very architecture of our bodies: tail remnants, vestigial organs, and a primitive metabolic system, we carry the seeds of our own weight difficulties.

To work with our bodies, rather than constantly fight them, we need to recreate the world in which our bodies developed. While we cannot participate in a primeval hunt, we can repeatedly, over a long period of time, consume only limited calories so that our bodies don't have to worry about getting enough food, but process the little they do get rapidly and efficiently.

Our little friends, the white rats in the laboratory mazes, have proven over and over again, that consistent undereating is the pathway to good health and longevity.

For all they did for mankind in the dawn of history, the cave dwellers deserve our thanks and our respect as do the bodies they left as their testimony.

What ungrateful abuse we heap on them when we allow ourselves to grow flabby and fat, desecrating their gift and nullifying their efforts.

What did our cavemen forbears bequeath as their legacy? Underfed and overactive, they willed us a body that still thinks we dwell in the primordial forest. Suddenly cut back on our intake of food and the alert is sounded through the nervous system and organs of our prehistoric physiology. "Famine coming, famine coming" our bodies shriek and immediately our metabolism slows to a crawl.