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While the law [of competition] may be sometimes hard for the individual, it is best for the race, because it insures the survival of the fittest in every department. We accept and welcome, therefore, as conditions to which we must accommodate ourselves, great inequality of environment, the concentration of business…
We live in a cultural milieu ... The idea that culture is our ecological niche is still applicable. The impact and force of natural selection on the human physique are conditioned by the dimensions of culture.
It's easy to see that predators (animals that kill and then eat other animals) are working for the downfall of their prey. But it's also true that prey are working for the downfall of their .fedators. They work hard to escape bei and it they all succeeded the predators would starve to death. The same thing holds…
Eventually, many billions of years ago, a molecule was formed that had a remarkable capability. It was able to produce, out of the molecular building blocks of the surrounding waters, a fairly accurate copy of itself. In such a molecular system there is a set of instructions, a molecular code, containing the sequence…
Charles Darwin's insights into natural selection have shown that there are no evolutionary pathways leading unerringly from simple forms to Man; rather, evolution proceeds by fits and starts, and most life forms lead to evolutionary dead-ends. We are the products of a long series of biological accidents. In the cosmic…
Foreshadowings of the principles and even of the language of [the infinitesimal] calculus can be found in the writings of Napier, Kepler, Cavalieri, Pascal, Fermat, Wallis, and Barrow. It was Newton's good luck to come at a time when everything was ripe for the discovery, and his ability enabled him to construct…
Evolution is neither moral nor immoral. It just is, and we make of it what we will. I have tried to show that two things we can make of it are that it’s simple and it’s marvelous. And far from constricting our actions, the study of evolution can liberate our minds. Human beings may be only one small twig on the vast…
Anybody who teaches human evolution is inevitably asked: Are we still evolving? The examples of lactose tolerance and duplication of the amylase gene show that selection has certainly acted within the last few thousand years. But what about right now? It’s hard to give a good answer. Certainly many types of selection…
One case involves our ability to digest lactose, a sugar found in milk. An enzyme called lactase breaks down this sugar into the more easily absorbed sugars glucose and galactose. We are born with the ability to digest milk, of course, for that’s always been the main food of infants. But after we’re weaned, we…
I am aware that the conclusions arrived at in this work will be denounced by some as highly irreligious; but he who denounces them is bound to shew why it is more irreligious to explain the origin of man as a distinct species by descent from some lower form, through the laws of variation and natural selection, than to…
We’ve always perceived ourselves as somehow standing apart from the rest of nature. Encouraged by the religious belief that humans were the special object of creation, as well as by a natural solipsism that accompanies a self-conscious brain, we resist the evolutionary lesson that, like other animals, we are…
True, breeders haven’t turned a cat into a dog, and laboratory studies haven’t turned a bacterium into an amoeba (although, as we’ve seen, new bacterial species have arisen in the lab). But it is foolish to think that these are serious objections to natural selection. Big transformations take time—huge spans of it. To…
A possible sequence of such changes begins with simple eyespots made of light-sensitive pigment, as seen in flatworms. The skin then folds in, forming a cup that protects the eyespot and allows it to better localize the light source. Limpets have eyes like this. In the chambered nautilus, we see a further narrowing of…
Here’s another prediction: under prolonged drought, natural selection will lead to the evolution of plants that flower earlier than their ancestors. This is because, during a drought, soils dry out quickly after the rains. If you’re a plant that doesn’t flower and produce seeds quickly in a drought, you leave no…
Still other species have adapted via selection to human-caused changes in their environment. Insects have become resistant to DDT and other pesticides, plants have adapted to herbicides, and fungi, worms, and algae have evolved resistance to heavy metals that have polluted their environment. There almost always seem…
We can even see the origin of new, ecologically diverse bacterial species, all within a single laboratory flask. Paul Rainey and his colleagues at Oxford University placed a strain of the bacteria Pseudomonas fluorescens in a small vessel containing nutrient broth, and simply watched it. (It’s surprising but true that…
But “laboratory” adaptations can also be more complex, involving the evolution of whole new biochemical systems. Perhaps the ultimate challenge is simply to take away a gene that a microbe needs to survive in a particular environment, and see how it responds. Can it evolve a way around this problem? The answer is…
... moving randomly through space, like dust motes in a sunbeam, colliding, hooking together, forming complex structures, breaking apart again, in a ceaseless process of creation and destruction. There is no escape from this process. ... There is no master plan, no divine architect, no intelligent design. All things…
A good example of bad design is the flounder, whose popularity as an eating fish (Dover sole, for instance) comes partly from its flatness, which makes it easy to bone. There are actually about 500 species of flatfish— halibut, turbot, flounders, and their kin—all placed in the order Pleuronectiformes. The word means…
It’s important to realize, though, that there’s a real difference in what you expect to see if organisms were consciously designed rather than if they evolved by natural selection. Natural selection is not a master engineer, but a tinkerer. It doesn’t produce the absolute perfection achievable by a designer starting…