p.11 Darwin's notion of natural selection can be enthroned in God's stead as the creative agency... Selection
slips into place as an agency creating order from chaotic variation.
p.31 Borrowing a culminating phrase from my colleagues N. Packard and C. Langton, life exists at the edge
of chaos.
p.33,34 As Jacob pointed out in "Evolution and Tinkering" (1977a; see also Jacob 1983), adaptation
typically progresses through small changes involving a local search in the space of possibilities. The paradigm is
one of local hill climbing via fitter mutants toward some local or global optimum... In this framework, adaptive evolution
in a population is a hill-climbing process... It is intuitive from this description that the behavior of an adapting
population depends on how mountainous the fitness landscape is, on how large the population is, and on the mutation rate
p.118 Adaptive evolution is a search process - driven by mutation, recombination, and selection
- on fixed or deforming fitness landscapes. An adapting population flows over the landscape under these forces.
The structure of such landscapes, smooth or rugged, governs the evolvability of populations and the sustained fitness of their
members. The structure of fitness landscapes inevitably imposes limitations on adaptive search.