Researchers studying niche construction commonly embrace an alternative perspective in which niche construction is regarded as a fundamental evolutionary process in its own right. Evolution entails networks of causation and feedback in which previously selected organisms drive environmental changes, and organism-modified environments subsequently select for changes in organisms.
The perspective is intellectually aligned with several other movements within evolutionary biology, including ‘developmental systems theory’ (Oyama et al. 2001), the active role of behavior (Bateson 1988), and of developmental plasticity (West-Eberhard 2003), in evolution, and calls for an extended evolutionary synthesis (Pigliucci & Muller 2010; Laland et al. 2015).
The extended evolutionary synthesis, or EES, is a new way to think about and understand evolutionary phenomena that differs from the conception that has dominated evolutionary thinking since the 1930s (i.e. the modern synthesis). It is a developing line of contemporary evolutionary thought that exists within the field of evolutionary biology.
According to the EES, explaining the origin of adaptations requires understanding how developmental processes generate heritable phenotypic variants from genetic, epigenetic and environmental inputs. Developmental bias and phenotypic plasticity play central roles in the EES as generators of novel, yet potentially functional and coordinated, phenotypic variation. This conception of bias is different from the traditional characterization of developmental constraints: rather than accounting for the absence of evolution or adaptation, developmental bias is also a source of adaptive variation.
Developmental bias and niche construction are, in turn, recognized as evolutionary processes that can initiate and impose direction on selection. Extra-genetic inheritance mechanisms (which include ecological inheritance) interact with genetics and environmental inputs to construct the developing organism, thereby contributing to the similarity between ‘transmitting’ and affected individuals.
Like niche construction theory, the EES emphasizes how organisms shape and are shaped by selective and developmental environments (reciprocal causation), and how the development of organisms is not programmed but open-ended and constructive (constructive development). Developmental processes, operating through developmental bias and niche construction, are viewed as sharing with natural selection some responsibility for the direction and rate of evolution and contribute to organism–environment complementarity.
The resulting network of processes provides a considerably more complex account of evolutionary mechanisms than traditionally recognized. The EES entails not only new research directions but also new ways to think about, and interpret, new and familiar problems in evolutionary biology.
Laland KN, Uller T, Feldman MW, et al. 2014 Does evolutionary theory need a rethink? Nature 514:161–164 Provides a very brief introduction to the motivation for an extended evolutionary synthesis.
Laland KN, Uller T, Feldman MW, et al. 2015 The extended evolutionary synthesis: its structure, assumptions and predictions. Phil Trans R Soc B. A detailed rationale for an extended evolutionary synthesis, outlining key assumptions, themes, novel predictions and how the EES differs from the MS.
