Adaptive recursion is a term borrowed from computer science.
A recursive algorithm is a program that runs a new
version of itself, by calling itself as it runs. Such recursion
can be used, for instance, when searching down a directory
tree, or, in the case of adaptive algorithms, to optimize an
outcome (Smithies et al. 2004). There are obvious parallels
between adaptive algorithms and biological adaptation.
Adaptive recursion in computing involves a repeated process,
the repeat being dependent upon on the preceding repeat
in a particular way. In biological adaptation the
“adaptive recursion” is the cycle from gene sequences to
their unfolding as functional phenotypes that then interact
with the environment leading to gene frequency change in
natural populations, and so back to a different starting set of
gene sequences. The programme then repeats in a manner
that is dependent on the previous iteration. In computing it is
important to avoid an infinite loop. In biology however the
recursion is potentially infinite, only terminated on extinction.