Glossary of Evolution (2nd ed.) by Futuyma (2009)
- A process of genetic change in a population whereby, as a result of natural selection, the average state of a character becomes improved with reference to a specific function, or whereby a population is thought to have become better suited to some feature of its environment. Also, an adaptation: a feature that has become prevalent in a population because of a selective advantage conveyed by that feature in the improvement in some function.
Glossary of Ecology (6th ed.) by Krebs (2009)
- any alteration in the structure or function of an organism by which the organism becomes better able to survive and multiply in its environment.
Glossary of Campbell Biology (7th ed.) by Campbell & Reece (2005)
Glossary of Campbell Biology (8th ed.) by Campbell et al. (2008)
Glossary of The Cell (5th ed.) by Alberts et al. (2008)
- Alberts, B., Johnson, A., Lewis, J. Raff, M., Roberts, K. & Walter P. 2008. Molecular Biology of the Cell, 5th ed. -xxxiii + 1268 pp. Garland Science, New York.
- Campbell, N. A. & Reece, J. B. 2005. Biology, 7th ed. -xl + 1231 pp. Pearson Benjamin Cummings, San Francisco.
- Campbell, N. A., Reece, J. B., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. & Jackson, R. B. 2008. Biology, 8th ed. -xlvi + 1267 pp. Pearson Benjamin Cummings, San Francisco.