Quotes About Variation

Well, at different points of people's careers or lives or circumstances, things are different.

Islands are known to differ in the food supply available to ground finches, mainly seeds.

Every actor wants to have a character that changes, that has some kind of movement, that gets from point A to point B, that doesn't just supply one note.

Sometimes the eye gets so accustomed that if you don't have a change, you're bored. It's the same with fashion, you know. And that, I suppose, is what style is about.

Si el universo en que han vivido los hombres de los tiempos pasados no tuviera nada en común con éste en que vivo; si esos dos universos no aparecieran, para un cierto grado de abstracción, como variaciones de un mismo tema, el universo del otro me resultaría radicalmente extraño y perdería todo significado. Para que la historia entera me resulte inteligible, los vivos deben descubrirse un cierto parentesco con los muertos.

Some days I feel like playing it smooth. Some days I feel like playing it like a waffle iron.

There is bound to be variation in the population of males in their predisposition to be faithful husbands. If females could recognize such qualities in advance, they could benefit themselves by choosing males possessing them. One way for a female to do this is to play hard to get for a long time, to be coy. Any male who is not patient enough to wait until the female eventually consents to copulate is not likely to be a good bet as a faithful husband.

Darwinism is not a theory of random chance. It is a theory of random mutation plus non-random cumulative natural selection. . . . Natural selection . . . is a non-random force, pushing towards improvement. . . . Every generation has its Darwinian failures but every individual is descended only from previous generations' successful minorities. . . . [T]here can be no going downhill - species can't get worse as a prelude to getting better. . . . There may be more than one peak.

if a design is good enough to evolve once, the same design principle is good enough to evolve twice, from different starting points, in different parts of the animal kingdom.

however many ways there may be of being alive, it is certain that there are vastly more ways of being dead, or rather not alive. You may throw cells together at random, over and over again for a billion years, and not once will you get a conglomeration that flies or swims or burrows or runs, or does anything, even badly, that could remotely be construed as working to keep itself alive.

natural selection is daily and hourly scrutinizing, throughout the world, every variation, even the slightest; rejecting that which is bad, preserving and adding up all that is good; silently and insensibly working, whenever and wherever opportunity offers, at the improvement of each organic being.

There is no universally agreed definition of a gene.

A gene is not indivisible, but it is seldom divided. It is either definitely present or definitely absent in the body of any given individual. A gene travels intact from grandparent to grandchild, passing straight through the intermediate generation without being merged with other genes. If genes continually blended with each other, natural selection as we now understand it would be impossible.

Evolution is the process by which some genes become more numerous and others less numerous in the gene pool.

As I said, the active/passive distinction cuts across the germ-line/dead-end distinction. All four combinations are conceivable.

A gene is defined as any portion of chromosomal material that potentially lasts for enough generations to serve as a unit of natural selection.

The earliest form of natural selection was simply a selection of stable forms and a rejection of unstable ones.

It is fundamental to the idea of a replicator that when a mistake or 'mutation' does occur it is passed on to future copies: the mutation brings into existence a new kind of replicator which 'breeds true' until there is a further mutation

From the viewpoint of this book an animal artefact, like any other phenotypic product whose variation is influenced by a gene, can be regarded as a phenotypic tool by which that gene could potentially lever itself into the next generation.

somebody who thinks natural selection is a theory of chance whereas—in the relevant sense of chance—it is the opposite.

In that case there must have been genes controlling variation in caddis houses, for selection cannot produce adaptations unless there are hereditary differences among which to select.

Natural selection may usually be safely regarded as the differential survival of replicators relative to their alleles.

The word allele is nowadays customarily used of cistrons but it is clearly easy, and in the spirit of this chapter, to generalize it to any portion of chromosome.

A stick insect looks like a replicator, in that we may lay out a sequence consisting of daughter, granddaughter, great-granddaughter, etc., in which each appears to be a replica of the preceding one in the series. But suppose a flaw or blemish appears somewhere in the chain, say a stick insect is unfortunate enough to lose a leg. The blemish may last for the whole of her lifetime, but it is not passed on to the next link in the chain.