Quotes from Brian Charlesworth

The combined effects of mutation, natural selection and the random process of genetic drift cause changes in the composition of a population. Over a sufficiently long period of time, these cumulative effects alter the population's genetic make-up, and can thus greatly change the species' characteristics from those of its ancestors.

The first way that selection can cause ageing is to keep early-acting mutations rare in populations, while allowing ones with effects late in life to become common.

A very much larger number have existed over the past history of life, owing to the fact that the ultimate fate of nearly all species is extinction, as described in Chapter 4.)

Selection is also important in non-biological contexts. In designing machines and computer programs, it has been found that a very efficient way to find the optimal design is to successively make small, random changes to the design, keeping versions that do the job well, and discarding others. This is increasingly being used to solve difficult design problems for complex systems. In this process, the engineer does not have a design in mind, but only the desired function. Adaptations

The combined effects of mutation, natural selection and the random process of genetic drift cause changes in the composition of a population. Over a sufficiently long period of time, these cumulative effects alter the population's genetic make-up, and can thus greatly change the species' characteristics from those of its ancestors. We

The speedy evolution of antibiotic resistance is not surprising, because bacteria multiply fast and are present in enormous numbers, so that any mutation that can make a cell resistant is sure to occur in a few bacteria in a population; if the bacteria are able to survive the change to their cell functions caused by the mutation and to multiply, a resistant population can rapidly build up.

Such a process of change will be especially likely if a population is exposed to a changed environment, where a somewhat different set of characteristics is favoured from those already established by selection.