Equilibrioception, the sense of a balance present in human beings and animals Equilibrium unfolding, the process of unfolding a protein or RNA molecule by gradually changing its environment Genetic equilibrium, theoretical state in which a population is not evolving Homeostasis, the ability of an open system, especially living organisms, to regulate its internal environment Punctuated equilibrium, theory in evolutionary biology Sedimentation equilibrium, analytical ultracentrifugation method for measuring protein molecular masses in solution Equilibrium Theory (Island biogeography), MacArthur-Wilson theory explaining biodiversity character of ecological islands Osmotic equilibrium