Quotes About Evolution

compared to that of great apes, the reduction in human gut size saves humans at least 10 percent of daily energy expenditure: the more gut tissue in the body, the more energy must be spent on its metabolism.

In addition to having a small gape, our mouths have a relatively small volume—about the same size as chimpanzee mouths, even though we weigh some 50 percent more than they do. Zoologists often try to capture the essence of our species with such phrases as the naked, bipedal, or big-brained ape. They could equally well call us the small-mouthed ape.

So the question of our origins concerns the forces that sprung Homo erectus from their australopithecine past. Anthropologists have an answer. According to the most popular view since the 1950s there was a single supposed impetus: the eating of meat.

Brillat-Savarin and Symons were right to say that we have tamed nature with fire. We should indeed pin our humanity on cooks.

Are we just an ordinary animal that happens to enjoy the tastes and securities of cooked food without in any way depending on them? Or are we a new kind of species tied to the use of fire by our biological needs, relying on cooked food to supply enough energy to our bodies?

History is far more important than evolutionary theorizing as a reminder about human potential, because the historical evidence of change is so much more vivid.

In 1995 Leslie Aiello and Peter Wheeler proposed that the reason some animals have evolved big brains is that they have small guts, and small guts are made possible by a high-quality diet. Aiello and Wheeler's head-spinning idea came from the realization that brains are exceptionally greedy for glucose—in other words, for energy. For an inactive person, every fifth meal is eaten solely to power the brain.

the implication is clear: there is something odd about us. We are not like other animals. In most circumstances, we need cooked food.

When we eat, our metabolic rate rises, the maximum increase averaging 25 percent. The corresponding figures for fish (136 percent) and for snakes (687 percent) are vastly higher, showing that humans pay less for digestion than other species, presumably due partly to our food being cooked. But the cost of digestion is still significant for humans and can be reduced or raised depending on the food type.

The moral contradictions of our ancestry should not prevent us from reaching a realistic assessment of who we are. Whehn we do that, high hopes are still possible.

Without the learned skills passed down to us by previous generations, we are in trouble. With them, we dominate the planet.

Human competitiveness still has elements of the primate system of achieving status by individual combat.

Many tendencies that we regard as morally reprehensible clearly evolved, including numerous kinds of sexual coercion, lethal violence, and social domination. Equally, many morally delightful tendencies did not evolve, such as charity to strangers and kindness to animals.

The evidence that Homo sapiens have been self-domesticating for three hundred thousand years, and how it happened, suggests that we are a thoroughly unusual primate.

The moral sense was once explained purely by religion. Now an evolutionary account is needed.

Coalitionary proactive aggression in humans, therefore, is most simply understood as an elaboration of ancient tendencies.

We know that over time society sometimes improves in quality, and sometimes decays. What we cannot know is which direction our descendants will take.

The moral contradictions of our ancestry should not prevent us from reaching a realistic assessment of who we are. When we do that, high hopes are still possible.

Pride, ideology, or belief restrains many people from viewing Homo Sapiens as just another primate species, one among many.

The control of fire and the practice of cooking are human universals.

Cooking was a great discovery not merely because it gave us better food, or even because it made us physically human. It did something even more important: it helped make our brains uniquely large, providing a dull human body with a brilliant human mind.

wild fruits are not nearly as rewarding as those domesticated fruits. The edible pulp of a forest fruit is often physically hard, and it may be protected by a skin, coat, or hairs that have to be removed. Most fruits have to be chewed for a long time before the pulp can be fully detached from the pieces of skin or seeds, and before the solid pieces are mashed enough to give up their valuable nutrients.

Hadza men were close to the average, spending more than 4 hours a day hunting—about eighty times as long as an Ngogo chimpanzee.

Males have evolved to possess strong appetites for power because with extraordinary power males can achieve extraordinary reproduction.