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Evolution
The World of Darwin
Adaptation
Adaptations
An adaptation is any genetically coded aspect of the outward physical or behavioral manifestation of an organism that increases the chances of that gene(s) being passed on to the next generation.

Any gene whose product increases the chances of that individual reaching reproductive maturity has a positive effect. Any gene whose product has a negative effect on reproductive success decreases that individual's reproductive chances.

The genotype of an individual, which includes all its genes taken collectively, is either a positive combination, or a negative one.

Fitness Reproductive success of gene combinations is measured using fitness, which is the probability of an individual contributing all or part of its genotype to its following generations..

A low fitness value means that there is little likelihood of an individual surviving long enough to reproduce, whereas a high fitness value means that there is a good chance for an individual to pass its genes onto its offspring.

Every aspect of an organism's phenotype is, in a way, an adaptation; therefore, the individual that results from all these genes, and gene products, is an interlocking mesh of overlapping structural, behavioral and metabolic adaptations.

These adaptations enable the organism to acquire energy, escape danger, exchange gases, replenish its stores of energy and materials, and so on. As one generation passes on its genes to the next generation, the codes for these successful adaptations are passed on too.


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© 2001, Professor John Blamire