Quotes about evolution

"Broadly speaking, the ability of the park is to control the spread of life forms. Because the history of evolution is that life escapes all barriers. Life breaks free. Life expands to new territories. Painfully, perhaps even dangerously. But life finds a way." Malcolm shook his head. "I don't mean to be philosophical, but there it is."

Evolution doesn’t happen without pain or loss. A lot of fish died, in order for a few to stand. The price may be worthwhile…

One great mystery is why sexual reproduction became dominant for higher life-forms. Optimization theory says it should be otherwise.

Take a fish or lizard, ideally suited to her environment, with just the right internal chemistry, agility, camouflage—whatever it takes to be healthy, fecund, and successful in her world. Despite all this, she cannot pass on her perfect characteristics. After sex, her offspring will be jumbles, getting only half of their program from her and half their re-sorted genes somewhere else.

Sex inevitably ruins perfection. Parthenogenesis would seem to work better—at least theoretically. In simple, static environments, well-adapted lizards who produce duplicate daughters are known to have advantages over those using sex.

Yet, few complex animals are known to perform self-cloning. And those species exist in ancient, stable deserts, always in close company with a related sexual species.

Sex has flourished because environments are seldom static. Climate, competition, parasites—all make for shifting conditions. What was ideal in one generation may be fatal the next. With variability, your offspring get a fighting chance. Even in desperate times, one or more of them may have what it takes to meet new challenges and thrive.

Each style has its advantages, then. Cloning offers stability and preservation of excellence. Sex gives adaptability to changing times. In nature it is usually one or the other. Only lowly creatures such as aphids have the option of switching back and forth.

We are programmed to find sex pleasurable for one simple reason—because animals who mate have offspring. Those who do not mate have none. Traits that result in successful reproduction get reinforced and passed on. Evolution is that simple.

It is therefore useless to bemoan as evil the fact that men tend toward aggression. Among our ancestors, aggression often helped males have more offspring than their competitors. “Good” and “evil” had little to do with it.

That is, until we reached consciousness, at which point, good and evil became pertinent indeed! Behaviors which might be excusable in dumb beasts can seem perverted, criminal, when performed by thinking beings. Just because a trait is “natural” does not oblige us to keep it.

Some researchers have speculated that religion itself may have played an important role in getting large groups of prehistoric humans to socially cohere. If this is true, we can say that religion has served an important purpose. This does not suggest, however, that it serves an important purpose now. There is, after all, nothing more natural than rape. But no one would argue that rape is good, or compatible with a civil society, because it may have had evolutionary advantages for our ancestors. That religion may have served some necessary function for us in the past does not preclude the possibility that it is now the greatest impediment to our building a global civilization.

Everything that exists, yearns to live. That's what the cycle of life is all about. That's the engine that drives the great biological pumps of evolution. Everything tries to inch its way up the tree, clawing or tentacling or sliming its way up to the next niche until it gets to the very top—which, on the whole, never seems to have been worth all that effort. (p. 81)

Relentless Pleistocene selection was shaping everything that would make up humanity. Even love was a by-product of evolution. Love, and the pain of loss.

A growing belief that behind every event lay intention—be it an evil thought in the mind of another, or the benevolent whim of a god in the sky—was perhaps inevitable in creatures with an innate understanding of causality. If you were smart enough to make multicomponent tools, you eventually came to believe in gods, the end of all causal chains. There would be costs, of course. In the future, to serve their new gods and shamans, the people would have to sacrifice much: time, wealth, even the right to have children. Sometimes they would even have to lay down their lives. But the payback was that they no longer had to be afraid of dying.

But even if it is true, even if we are governed by the legacy of an animal past, then it is up to us to behave as if it were not so.

The emergent humans were still animals, still bound by natural law. No innovation in the way they lived would have taken root if it had not given them an adaptive advantage in the endless struggle to survive. An ability to believe in things that weren’t true was a powerful tool.

There was no design in this: no sense of improvement, of purpose. All that was happening was that each organism was struggling to preserve itself, its offspring, and its kin. But as the environment slowly changed, so through relentless selection did the species that inhabited it. It was not a process fueled by life, but by death: the elimination of the less well adapted, the endless culling of inappropriate possibilities. But the potential of an unseen future was no consolation to those who lived through the relentless culling.

If you were part of a group there was always the chance that the predator would take the next guy, not you. It was a cold-blooded lottery that paid off often enough to be worthwhile adapting for.

But there were disadvantages to group living: mainly, if there were large numbers of you, there was increased competition for food. As that competition resolved itself, the inevitable result was social complexity—and the size of the adapids’ brains had increased so that they were capable of handling that complexity. Then, of course, they were forced to become even more efficient at searching for food to fuel those big brains.

It was the way of the future. As primate societies became ever more complex, a kind of cognitive arms race would continue, increasing smartness fueled by increasing social complications.