Termite dispersal is influenced by their diet

Area of Science:

• Ecology
• Evolutionary Biology
• Zoology

Background:

• Termites are detritivores found globally, feeding on plant matter.
• Wood-feeding termites are efficient oceanic dispersers, while soil-feeders are considered poor dispersers.
• The wide distribution of soil-feeding termites across continents necessitates an explanation for their dispersal capabilities.

Purpose of the Study:

• To reconstruct the historical biogeography of termites.
• To determine the ancestral diet of termite lineages.
• To explain the transoceanic distribution patterns of both wood- and soil-feeding termites.

Main Methods:

• Analysis of mitochondrial genomes from 324 termite samples across five biogeographic realms.
• Stable isotope measurements (δ¹³C and δ¹⁵N) to infer diet.
• Biogeographic modeling and ancestral range reconstruction.

Main Results:

• Biogeographic models confirmed wood-feeders possess greater oceanic dispersal ability than soil-feeders.
• Wood-feeders were found on remote islands lacking soil-feeders, supporting their superior dispersal.
• Ancestral range reconstructions revealed 33 intercontinental dispersal events, with 18 attributed to soil-feeders.

Conclusions:

• Soil-feeding termites, despite their presumed low dispersal ability, have been significant agents of transoceanic dispersal.
• Multiple dispersals by soil-feeders have substantially influenced the current global distribution of termites.
• This study revises our understanding of termite dispersal mechanisms and biogeography.