Glossary of "Evolution (4th ed.)" by Futuyma & Kirkpatrick (2017)
- An unchanging condition, as of population size or genetic composition. Also, the value (e.g., of population size, allele frequency) at which this condition occurs. An equilibrium need not be stable. See stability, unstable equilibrium.
Glossary of "Life (9th ed.)" by Sadava et al. (2011)
- Any state of balance opposing forces and no net change.
Glossary of "Environmental Science: Earth as a Living Planet (2nd ed.)" by Botkin & Keller (1998)
- A point of rest. A system that does not tend to undergo any change of its own accord but remains in a single, fixed condition is said to be in equilibrium. Compare with steady state.
- Botkin, D. B. & Keller, E. A. 1998. Environmental Science: Earth as a Living Planet, 2nd ed. -xxxxii + 649 pp. John Wiley & Sons, Inc., New York.
- Futuyma, D. J. & Kirkpatrick, M. 2017. Evolution, 4th ed. -xviii + 602 pp. Sinauer Associates, Inc., Sunderland.
- Sadava, D., Hillis, D. M., Heller, H. C. & Berenbaum, M. R. 2011. Life: The Science of Biology, 9th ed. -xliv + 1266 pp. Sinauer Associates, Inc., Sunderland.