I distinguish two forms of pluralism about biological functions, between-discipline pluralism and within-discipline pluralism. Between-discipline pluralism holds that different theories of function are appropriate for different subdisciplines of biology and psychology. I provide reasons for rejecting this view. Instead, I recommend within-discipline pluralism, which emphasizes the plurality of function concepts at play within any given subdiscipline of biology and psychology.

A hypothesis of genome structural evolution is explored. Rapid and cohesive alterations in genome organization are viewed as resulting from the dynamic and constrained interactions of chromosomal subsystem components. A combination of macromolecular boundary conditions and DNA element involvement in far-from-equilibrium reactions is proposed to increase the complexity of genomic subsystems via the channelling of genome turnover; interactions between subsystems create higher-order subsystems expanding the phase space for further genetic evolution. The operation of generic constraints on structuration in genome evolution (...) is suggested by i) universal, homoplasic features of chromosome organization and ii) the metastable nature of genome structures where lower-level flux is constrained by higher-order structures. Phenomena such as ‘genomic shock’, bursts of transposable element activity, concerted evolution, etc., are hypothesized to result from constrained systemic responses to endogenous/exogenous, micro/macro perturbations. The constraints operating on genome turnover are expected to increase with chromosomal structural complexity, the number of interacting subsystems, and the degree to which interactions between genomic components are tightly ordered. (shrink)