The word selection can be confusing, because its common usage implies choice: I’m selecting this over that. In reality, the concept means that the more favorable a trait is for a particular environment, the higher the chance of that organism living long enough to procreate. Biologist Geerat J. Vermeij describes it as “nonrandom elimination.

Selection does not work by cutthroat competition between individuals, but by favouring whatever behavior is useful to the group. People with crude notions of "Darwinism" make an intriguing blunder here. They refuse the mere fact of competing, that is, of needing to share out a resource with the motive of competitiveness or readiness to quarrel.

Theory of selection /.../ leaves untouched all that can be inferred from the existence of the conditions which make organic evolution possible: matter which lives, multiplies, and varies ; an environment which possesses the marvellously complex constitution required to make these processes possible. /.../ it cannot produce either the original environment or the original living matter. These must be due either to luck or to contrivance; and, if they be due to luck, the luck (we must own) is great. How great we cannot say.

1. Both positive and negative selection leave distinctive signatures at the molecular level that can be detected using statistical tests. 2. In population genetic data, selection may affect levels of variability, linkage disequilibrium, haplotype structure and allelic distribution in each nucleotide site (frequency spectrum). In comparative data, selection has a strong effect on the dN/dS ratio. 3. Statistical methods for detecting selection differ in the assumptions they make and how powerful they are. Most methods applicable to population genetic data rely on strong assumptions regarding the demography of the populations, while comparative methods are free of such assumptions. 4. An increasing amount of evidence suggests that positive selection is much more pervasive than previously thought. 5. Inferences regarding selection provide a powerful tool in functional studies, for example for the prediction of possible disease-related genomic regions.

The last decade has seen a steady increase in the application of concepts from the theory of games to the study of evolution. Fields as diverse as sex ratio theory, animal distribution, contest behaviour and reciprocal altruism have contributed to what is now emerging as a universal way of thinking about phenotypic evolution.

Natural selection, as it is actually used in evolutionary population biology, serves mainly as an optimization process. In fact, the reasoning that underlies much evolutionary biology often strikes social scientists as strongly reminiscent of neoclassical economics.

Conceptual simplicity, recursiveness, and formal separation of levels of selection are attractive features of these equations. But, of course, being able to point to a relevant and generally non-zero part of selective change is far from showing that group selection can override individual selection when the two are in conflict. Moreover, even the possibility of devising model circumstances in which a positive group-selection term (first term) outweighs a negative individual selection one (second term, assuming no further levels), gives no guarantee that ‘altruism’ can evolve by group selection: we have to consider whether the population can get into the specified state, and, if it can, whether its present trend will continue.

Natural selection is all about the differential success of rival DNA in getting itself transmitted vertically in the species archives.

The theory of communication is partly concerned with the measurement of information content of signals, as their essential property in the establishment of communication links. But the information content of signals is not to be regarded as a commodity; it is more a property or potential of the signals, and as a concept it is closely related to the idea of selection, or discrimination. This mathematical theory first arose in telegraphy and telephony, being developed for the purpose of measuring the information content of telecommunication signals. It concerned only the signals themselves as transmitted along wires, or broadcast through the aether, and is quite abstracted from all questions of "meaning." Nor does it concern the importance, the value, or truth to any particular person. As a theory, it lies at the syntactic level of sign theory and is abstracted from the semantic and pragmatic levels. We shall argue … that, though the theory does not directly involve biological elements, it is nevertheless quite basic to the study of human communication -- basic but insufficient.

Sexual selection theory suggests that much of the behavior and some of the appearance of an animal is adapted not to help it survive but to help it to acquire the best or the most mates.

We may consequently state the fundamental theorem of Natural Selection in the form : The rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time.

Group selection theory would therefore predict a tendency to evolve towards an all-dove conspiracy ... But the trouble with conspiracies, even those that are to everybody's advantage in the long run, is that they are open to abuse.

To many, this doctrine of Natural Selection, or 'the preservation of favoured races in the struggle for life,' seems so simple, when once clearly stated, and so consonant with known facts and received principles, that they have difficulty in conceiving how it can constitute a great step in the progress of science. Such is often the case with important discoveries, but in order to assure ourselves that the doctrine was by no means obvious, we have only to refer back to the writings of skilful naturalists who attempted in the earlier part of the nineteenth century, to theorise on this subject, before the invention of this new method of explaining how certain forms are supplanted by new ones, and in what manner these last are selected out of innumerable varieties, and rendered permanent.

It has seemed to me that the theory (calcul) of probabilities ought to serve as the basis for the study of all the sciences, and particularly of the sciences of observation.