Persistence selection between simulated biogeochemical cycle variants for their distinct effects on the Earth system

Area of Science:

• Earth System Science
• Evolutionary Biology
• Biogeochemistry

Background:

• The long-term impact of Darwinian evolution on Earth's habitability is poorly understood.
• Existing models attempting to explain this through persistence-based selection on non-replicating biogeochemical processes lack mechanistic detail.

Purpose of the Study:

• To present a theoretical framework for understanding persistence selection in biogeochemical processes.
• To define and individuate biogeochemical cycle-biota-variants (CBVs) based on their environmental feedback mechanisms.
• To explore the relationship between CBV dynamics, evolutionary processes, and Earth system properties.

Main Methods:

• Definition of a biogeochemical cycle-biota-variant (CBV) as a biologically facilitated recycling pathway for essential elements.
• Identification of CBVs based on feedback effects of their climatic or geochemical side effects on persistence.
• Analysis of scale separation between CBV dynamics and conventional Darwinian evolution.
• Examination of threshold behavior in climate feedback and its impact on CBV-level competitive exclusion.
• Distinguishing CBV-level persistence selection from genotype-level selection via covariance analysis.

Main Results:

• A theoretical framework is established for defining and individuating CBVs.
• The framework reveals how scale separation can introduce randomness between CBVs and Earth system impacts.
• Threshold climate feedback can amplify biotic impacts and lead to CBV competitive exclusion.
• Persistence selection at the CBV level is observationally distinguishable from genotype selection.

Conclusions:

• The study demonstrates the theoretical coherence of persistence selection for non-replicating life-environment interactions.
• This framework has broad applicability in biogeochemistry and understanding Earth system evolution.
• While local selection may destabilize large-scale properties, persistence selection offers a new lens for analysis.