adaptation, geneticany characteristic that improves the chances of an organism transmitting GENES to the next generation (i.e. producing offspring). Such beneficial changes are genetically controlled and can be distinguished from alterations occurring within one generation (see ADAPTATION, PHYSIOLOGICAL) which may not lead to genetic change. Adaptations can affect any level of organization, from cells to whole organisms, and their behaviour. Adaptions are favoured by the process of NATURAL SELECTION.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005