Dispersal enhances beta diversity in nectar microbes.

Area of Science:

• Ecology
• Microbial Ecology
• Community Ecology

Background:

• Dispersal is a major factor influencing species composition variation (beta diversity) among communities.
• Empirical evidence testing the role of dispersal in driving beta diversity remains limited.
• Previous experiments often controlled dispersal, potentially overlooking its complex effects.

Discussion:

• This study manipulated microbial dispersal via flower-visiting animals to assess its impact on nectar-inhabiting bacteria and yeasts.
• Contrary to the common assumption that dispersal reduces beta diversity, higher dispersal led to increased variation in microbial communities.
• This unexpected outcome is potentially explained by stronger priority effects when dispersal is less limited.

Key Insights:

• Microbial beta diversity was highest when dispersal was least limited, challenging existing ecological paradigms.
• Stochastic dispersal creates varied species arrival histories, promoting community divergence through priority effects.
• Priority effects, where early colonizers influence subsequent community composition, appear amplified by increased dispersal.

Outlook:

• The positive influence of dispersal on beta diversity may be underappreciated in microbial, plant, and animal communities.
• Future research should explore the mechanisms and prevalence of dispersal-mediated priority effects.
• Understanding dispersal's role is crucial for predicting community dynamics and biodiversity patterns.