Conserved, yet disruption-prone, gut microbiomes in neotropical bumblebees.

Area of Science:

• Ecology
• Evolutionary Biology
• Microbiology

Background:

• Social bees, crucial pollinators, serve as key models for studying gut microbiome ecology and evolution.
• Most research focuses on temperate managed bees, leaving neotropical wild bee microbiomes understudied.
• Neotropical bumblebees harbor ancient, specific, and beneficial gut symbionts.

Purpose of the Study:

• To characterize the gut microbiomes of wild neotropical bumblebee communities in Colombia.
• To identify drivers of gut microbiome structure in neotropical bumblebees.
• To compare microbiome structure between neotropical and temperate bumblebees.

Main Methods:

• 16S rRNA gene sequencing was employed to analyze gut bacterial communities.
• Data from neotropical bumblebees were analyzed alongside published data from temperate bumblebees.
• Drivers of microbiome structure were investigated across diverse bumblebee populations.

Main Results:

• Neotropical bumblebee lineages maintained ancient gut bacterial symbionts during North American dispersal.
• Major gut microbiome disruptions were observed in neotropical bumblebees, strongly associated with parasite infection.
• Host phylogeny was a more significant determinant of microbiome structure than geographic location.

Conclusions:

• Bumblebee gut microbiomes exhibit resilience in retaining ancient symbionts but are vulnerable to disruption by parasites.
• Host evolutionary history, reflected in phylogeny, plays a dominant role in structuring gut microbiomes over environmental factors.
• Understanding these dynamics is crucial for bumblebee conservation and pollination ecology.