The Dialectics of Biospheric Evolution
David Schwartzman
For the strict NeoDarwinian the biosphere cannot evolve in the sense that the biota evolves.But lets explore the consequences of considering theanaloguesof genotype and phenotype in the biosphere itself. My six theses on biospheric evolution:
1. The biosphere is a "complex adaptive system", adapting to changing external abiotic constraints (e.g., solar luminosity, volcanic outgassing rate) but also self-adapting (e.g., creating new steady-states) and self-selecting (e.g., the thermophile and oxygen catastrophes of surface ecosystems).
2. The biosphere is a self-organizing complex whole. The interpenetration of its parts and its whole includes the nonlinear interaction of the parts, its network of positive and negative feedbacks, the continual reshaping of the parts by the whole, the history of the whole recorded in its parts, transients and steady-states etc. The whole: biosphere; the parts: ocean, upper crust, clouds, surface ecosystems, etc.The failure to recognize the dialectical interaction of the whole and parts leads to the errors of "holism" and reductionism, e.g., holism: the biosphere itself is a living organism; e.g., reductionism: there are no emergent properties of the biosphere.
3. The genotype of the biosphere: its material inheritance, the sum total of all its parts, embodying its history (genetically coded or preserved). The phenotype of the biosphere: its activity, its metabolism, its biogeochemical cycles. The genotype of the biosphere is the cumulative product of its phenotypes since the origin of life.
4. The history of the phenotypes of the biosphere is recorded in its parts, e.g., paleobiology and geochemistry of sedimentary rocks, and genome of the biota.
5. The Gaian character of biospheric evolution: the tight coupling of the abiotic and biotic components, its self-regulation; Vernadskian character: progressive changes in biospheric history, "life as a geological force".
6. The evolution of the biosphere self-selects a pattern of biotic evolution that is quasi-deterministic. The challenge: develop a theory of the biosphere from raw material of research on epigenetics with Lamarckian-like inheritance in ecosystems, niche construction, higher level natural selection, and the metatheories of emergence, self-organization, complexity and systems. Now on the astrobiological agenda: explore and create the theory of comparative biospheres.
References
Levins, R. and R. Lewontin, 1985.The Dialectical Biologist, Harvard University Press, Cambridge.
Schwartzman, D. 1999, 2002.Life, Temperature, and the Earth: The Self-Organizing Biosphere. New York: Columbia University Press.
Schwartzman, D. 2015. From the Gaia hypothesis to a theory of the evolving self-organizing biosphere.Metascience: Published Online.DOI 10.1007/s11016-014-9979-3.