| Nonlinear Dynamics, Psychology, and Life Sciences, Vol. 11, Iss. 4, Oct, 2007, pp. 413-433 @2007 Society for Chaos Theory in Psychology & Life Sciences Principal Difference Between Stability and Structural Stability (Robustness) as Used in Systems Biology Abstract: The concepts stability and structural stability (robustness) are
used often in systems biology. According to Kitano (2004) robustness is a
fundamental property of evolvable complex biological systems. For
that reason, the purpose of this review is to clarify: (a) how are
strictly formulated concepts, such as stability and robustness of a
dynamical system, used in computational systems biology; (b) what is
meant by structural stability (robustness) in contemporary biology and
how are stability and robustness distinguished from each other; and (c)
why is it necessary to investigate whether a cell signal pathway is stable.
We formulate the two concepts stability and structural stability (robustness)
of a dynamical system with an arbitrary dimensionality, in the way they are
known in mathematics and mechanics, and clarify the principal difference
between them. We also consider how these two concepts are used in the
analysis of a concrete biological system in systems biology. In the last
section we formulate when, according to us, in biology (and in systems
biology in particular), it should be said that a system (process) is stable,
and when it is structurally stable. Keywords: stability, robustness, systems biology |