Spatio-temporal variation of Cerambycidae-host tree interaction networks

Area of Science:

• Ecology
• Entomology
• Forest Science

Background:

• Commensal interactions, particularly between insects and plants, are crucial for ecosystem function but remain understudied at the community level.
• Tropical dry forests (TDFs) exhibit high species diversity and seasonality, yet the influence of resource availability on commensal interaction patterns is poorly understood.

Purpose of the Study:

• To experimentally investigate how spatio-temporal resource availability affects the diversity, composition, and interaction patterns of saproxylic beetles and their host trees in a Mexican TDF.
• To analyze the network structure of these interactions and relate them to species-level traits and wood characteristics.

Main Methods:

• Selected 65 host tree species and collected 16 wood sections per species for field exposure.
• Implemented four distinct spatio-temporal treatments to allow cerambycid oviposition.
• Analyzed interaction networks, calculating species-level indices and considering wood physical properties (hardness, decomposition rate) and beetle body size.

Main Results:

• Observed a nested and modular network structure with high specialization and significant turnover of cerambycid species and their interactions.
• Cerambycids predominantly associated with softwood species exhibiting lower decomposition rates and with more abundant host tree species.
• Despite high specialization, interactions were not static, with turnover driven by cerambycid emergence patterns influencing host plant selection.

Conclusions:

• Commensal interactions between cerambycids and host trees in TDFs are highly specialized yet exhibit significant spatio-temporal variation.
• The observed turnover in interactions is linked to cerambycid emergence timing and host preference.
• Understanding these spatio-temporal dynamics is vital for predicting how habitat changes may alter species composition and ecological interactions within TDFs.