Plasticity

A phenotype-centered view of evolution needs to start with a solid idea about the nature of the phenotype. This chapter and the next are devoted to two universal properties of phenotypes, plasticity, or responsiveness to environmental inputs; and modularity, or subdivision into semi-independent and dissociable parts (chapter 4). Of these two properties, plasticity is probably the more fundamental, for the ability to replicate, which distinguishes organic from inorganic nature, requires molecules which are interactive and precisely responsive— adaptively plastic. So plasticity must have been an early universal property of living things. The universality of modularity is a secondary, or “emergent” result of the…