Growth, death, and resource competition in sessile organisms

Area of Science:

• Theoretical Ecology
• Mathematical Biology
• Ecological Modeling

Background:

• Population-level scaling in ecological systems is a fundamental pattern.
• This scaling arises from individual growth, death, and competitive interactions.
• Existing models often lack a unified framework for spatiotemporal dynamics.

Purpose of the Study:

• To develop a minimal dynamical model explaining population-level scaling.
• To connect spatial patterns (regular and random) and temporal dynamics across sessile organisms.
• To unify diverse ecological phenomena under a single theoretical framework.

Main Methods:

• Developed a minimal dynamical model of metabolic growth.
• Incorporated individual growth, mortality, and resource competition (shared capture area).
• Varied parameters for growth, death, and competitive attrition to analyze spatiotemporal patterns.

Main Results:

• The model links individual growth/mortality tension to population size distribution.
• It connects regular and random spatial patterns across sessile organisms (forests, ants, termites, fairy circles).
• Asymmetric competition generates population shocks and demographic oscillations, matching forest data.

Conclusions:

• A minimal quantitative theory unifies spatiotemporal patterns in sessile organisms.
• Local competition, mediated by metabolic growth laws, is key.
• These growth laws are shaped by long-term evolutionary dynamics.