Exploring evolution of maximum growth rates in plankton

Area of Science:

• Ecological modeling
• Evolutionary biology
• Earth systems science

Background:

• Earth systems models often omit organism evolution, a key driver of species interactions and environmental dynamics.
• Planktonic activity is central to Earth systems, yet evolutionary adaptation is rarely incorporated into models.

Purpose of the Study:

• To simulate the evolution of maximum growth rate (μm) in plankton within Earth systems models.
• To investigate how evolutionary dynamics influence ecological and climate projections.

Main Methods:

• Developed a low-computational-cost approach to model the evolution of μm for plankton components.
• Integrated evolutionary dynamics into a Nutrient-Phytoplankton-Zooplankton (NPZ) model.
• Explored parameter ranges inducing environmental stresses that drive μm evolution.

Main Results:

• Simulations incorporating μm evolution yield different climate change projections compared to static models.
• Evolutionary adaptation can reshape growth and trophic dynamics, potentially leading to declines in primary production.
• The capacity for evolution supports 'evolutionary rescue,' suggesting current extinction predictions may be overstated.

Conclusions:

• Maximum growth rate evolution is crucial for accurate ecological and climate modeling.
• Ecosystem maturity and resource availability correlate with evolved maximum growth rates, explaining observed differences between species.
• Incorporating evolution provides a more realistic understanding of plankton dynamics and ecosystem responses to environmental change.