Segregation structure in Odonata assemblages follows the latitudinal gradient.

Area of Science:

• Ecology
• Biogeography
• Zoology

Background:

• Latitude significantly influences biodiversity, with species diversity generally increasing towards the tropics.
• Negative biotic interactions, such as competition and predation, are hypothesized to create checkerboard distribution patterns in species assemblages.
• Previous research has not established a clear link between checkerboard patterns and latitudinal gradients.

Purpose of the Study:

• To investigate the relationship between species segregation patterns and latitude in Odonata (dragonfly) assemblages globally.
• To determine if local species richness influences the occurrence of segregation patterns.
• To explore the drivers of the Latitudinal Diversity Gradient.

Main Methods:

• Utilized a global faunistic dataset of 395 Odonata species across 386 natural communities, spanning 87° latitude.
• Employed co-occurrence analyses, specifically the C-score index and Standardized Effect Size, to quantify checkerboardness.
• Correlated the observed segregation patterns with latitudinal data.

Main Results:

• Odonata assemblages exhibited segregation patterns more frequently at lower latitudes (towards the tropics).
• Regional species diversity followed the Latitudinal Diversity Gradient, but local community richness did not.
• Local species richness did not significantly affect the observed segregation patterns.

Conclusions:

• Species segregation in Odonata assemblages increases with decreasing latitude, suggesting a role for biotic interactions.
• The Latitudinal Diversity Gradient is influenced by factors beyond local species richness.
• Further research into ecological and historical processes is needed for a mechanistic understanding of latitudinal biodiversity patterns.