Biodiversity maintenance may be lower under partial niche differentiation than under neutrality

Area of Science:

• Ecology
• Community Ecology
• Theoretical Ecology

Background:

• Niche differentiation is traditionally viewed as crucial for species coexistence.
• It is expected to increase species richness and persistence by reducing competition.
• However, the interplay between local dynamics and regional processes is complex.

Purpose of the Study:

• To investigate the impact of niche differentiation on species coexistence and community dynamics.
• To compare stochastic niche and neutral dynamics under local and regional influences.
• To determine conditions under which niche differentiation promotes or hinders species persistence.

Main Methods:

• Simulated ecological assemblages using stochastic niche and neutral models.
• Incorporated immigration from a regional species pool.
• Analyzed effects of trait variation, regional abundances, and intrinsic growth rates.

Main Results:

• Partial niche differentiation can protect some species but lead to the exclusion of others.
• Regional abundances and growth rates influence persistence similarly to niche differentiation.
• High niche availability is necessary to prevent increased extinction rates and reduced species richness.

Conclusions:

• Niche differentiation's effect on coexistence is more complex than previously assumed, especially with immigration.
• Distinctions between niche and neutral dynamics can be blurred by regional factors.
• Understanding community dynamics requires considering both local niche structure and regional species pool influences.