Adaptive plasticity in ontogenetic niche shifts stabilizes consumer-resource dynamics

Area of Science:

• Ecology
• Evolutionary Biology
• Theoretical Ecology

Background:

• Ontogenetic niche shifts, changes in diet or habitat during an organism's life, are common across taxa.
• These shifts create population stage structure, influencing interactions with different ecological communities and population dynamics.

Purpose of the Study:

• To mathematically model and test the hypothesis that adaptive plasticity in the timing of ontogenetic niche shifts stabilizes consumer-resource dynamics.
• To investigate how flexible timing of niche shifts, based on resource density, impacts population stability.

Main Methods:

• Comparison of three consumer-resource models: fixed-age shift, fixed-size shift, and adaptive plasticity shift.
• Mathematical modeling to analyze the stability of consumer-resource equilibria under different shift timing mechanisms.
• Focus on density-dependent negative feedback in resource dynamics as a stabilizing factor.

Main Results:

• Only the adaptive plasticity model demonstrated a locally stable equilibrium.
• Adaptive plasticity stabilizes dynamics by enabling early shifts when resources are scarce and delayed shifts when resources are abundant.
• This leads to density-dependent negative feedback, promoting resource recovery and population stability.

Conclusions:

• Adaptive plasticity in ontogenetic niche shifts is a key mechanism for stabilizing consumer-resource dynamics.
• This flexibility allows populations to better manage resource availability, preventing overexploitation and promoting long-term stability.
• Findings have implications for understanding the population dynamics of species like lake fish.