The Adaptation Front Equation Explains Innovation-Driven Taxonomic Turnovers and Living Fossilization.

Area of Science:

• Evolutionary biology
• Ecological dynamics
• Theoretical ecology

Background:

• Taxonomic turnovers are linked to innovations that provide advantages in ecological niches.
• Species can repeatedly diversify and migrate from optimal to suboptimal niches, impacting less innovative species.

Purpose of the Study:

• To develop an analytical model predicting innovation-driven species flow across niche spaces.
• To understand how species packing and adaptive dynamics influence evolutionary trajectories.

Main Methods:

• Combined species packing theory and adaptive dynamics theory.
• Developed an equation for analytical prediction of species flow.
• Utilized simulated evolution to validate the model.

Main Results:

• Central ecological niches (high carrying capacity) exhibit the fastest innovation rates, acting as biodiversity sources.
• Species diverging from central niches outcompete those in peripheral niches, leading to extinction or further migration.
• Peripheral niche species are least innovated, show deep divergence times, and represent "living fossils".

Conclusions:

• Innovation-driven species flow shapes biodiversity patterns across niche landscapes.
• Peripheral geographic regions are also predicted to harbor "living fossils".
• The model provides a framework for understanding evolutionary radiations and diversification dynamics.