Ecological divergence among colour morphs mediated by changes in spatial network structure associated with...

Area of Science:

• Ecology
• Animal Behavior
• Conservation Biology

Background:

• Individual behavior influences animal social interactions and population spatial structure.
• Habitat disturbance alters resource availability, potentially impacting social and ecological interactions.
• Resource limitation in disturbed habitats may lead to dominant individuals controlling resources, reflecting behavioral differences.

Purpose of the Study:

• To investigate how environmental disturbance affects the spatial organization and social network structure of male tree lizards (Urosaurus ornatus).
• To examine the interplay between habitat disturbance, individual behavior (aggression, dewlap polymorphism), and resource use in structuring animal populations.
• To assess variations in morphological, behavioral, and ecological traits in relation to disturbance levels and their impact on fitness.

Main Methods:

• Applied a network framework to analyze the spatial organization of male tree lizards at three sites with varying disturbance levels (unburned, infrequently burned, frequently burned).
• Quantified male aggressive behavior in laboratory settings.
• Compared body size, condition, bite marks, parasite load, microhabitat use, and diet among males across different sites and morphs.

Main Results:

• No significant differences in spatial network structure were found between unburned and infrequently burned sites.
• At the frequently burned site, the spatial network shifted towards geographically closer, heteromorphic male neighbor associations.
• Males at the frequently burned site were larger, more aggressive, had more bite marks, fewer parasites, and exhibited divergent microhabitat use and diet, with aggressive morphs dominating resources.

Conclusions:

• Environmental variation, particularly habitat disturbance, significantly influences animal spatial network structure.
• The combination of behavioral and environmental variation can promote despotic social dynamics and ecological divergence in resource-limited environments.
• Understanding these dynamics is crucial for predicting population responses to environmental change and managing wildlife populations.