Book answers age-old questions on what our genetic structure tells us about our bodies

"We now can look at our genes word by word, sentence by sentence, within the genetic structure, and they tell us the tale of where we came from and how we evolved,” Meller said.

In his book, Meller answers age-old questions such as: When is pain good for us? Why are we fat? How is gossip good for us? How does a pregnant woman’s morning sickness help her developing baby? Why are some women attracted to bad guys?

Meller believes that by arming ourselves with knowledge of how our bodies have evolved and where our behaviors came from, we can make better decisions on how we treat our bodies today.

Some of Meller’s ideas fly directly in the face of accepted theories.

"Think about it. If sunshine were so dangerous, how could Stone Age people have spent their entire lives outdoors, mostly naked, and not dropped like flies from skin cancer?” (Seventy-five percent of melanomas, the deadly kind of skin cancer, he said, are not caused primarily by sun exposure but by our genes.)

Water? Most of us are overhydrated, Meller said. "We do not need to drink so much. We never did.” (Most of the water our ancestors ingested came from food, he writes.)

But many of his hypotheses are logical conclusions drawn from the human condition, which he contends hasn’t changed much in hundreds of thousands of years.

"It’s not like we’re going to go back there to the Stone Age,” he said. "But our bodies, our genetic makeup and our evolutionary heritage are not going to change very fast.”

Here are a few of his other assertions.

In general, people have a great capacity for judging trustworthiness and honesty. In evolutionary medicine, when researchers find capabilities that people are very good at and spend a lot of time on, they look for reasons that skill might have been important in earlier times and been selected to evolve.

And most people are excellent at gossip, whether they admit it or not, Meller said.

"Interestingly enough, if you go back to one of the earliest written records that we have, the Ten Commandments, that record states ‘Thou shalt not bear false witness.’ It doesn’t say anything about bearing true witness. And this is gossip,” Meller said.

In general, gossip is looked at as a bad thing. But Meller contends gossip can be good because it tells us the limits of our society.

"It tells us who’s good and who’s bad, who we can trust, who’s going to cut and run when we really need them,” Meller said. "That’s what the real subject is. It’s all about sex, and it’s all about trustworthiness.”

How did cave people gossip? They likely spoke a rudimentary language with only about 1,000 words. "Ursprache” is the name scientists have given to one hypothetical primitive language. With only a basic vocabulary, Meller said, Stone Age people could communicate what they needed to know such as who was sleeping with whom, who got the bigger piece of meat, who stole food from whom and who was the dominant male.