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Abstract For most animals, the microbiome is key for nutrition and pathogen defence, and is often shaped by diet. Corbiculate bees, including honey bees, bumble bees, and stingless bees, share a core microbiome that has been shaped, at least in part, by the challenges associated with pollen digestion. However, three species of stingless bees deviate from the general rule of bees obtaining their protein exclusively from pollen (obligate pollinivores) and instead consume carrion as their sole protein source (obligate necrophages) or consume both pollen and carrion (facultative necrophages). These three life histories can provide missing insights into microbiome evolution associated with extreme dietary transitions. Here, we investigate, via shotgun metagenomics, the functionality of the microbiome across three bee diet types: obligate pollinivory, obligate necrophagy, and facultative necrophagy. We find distinct differences in microbiome composition and gene functional profiles between the diet types. Obligate necrophages and pollinivores have more specialized microbes, whereas facultative necrophages have a diversity of environmental microbes associated with several dietary niches. Our study suggests that necrophagous bee microbiomes may have evolved to overcome cellular stress and microbial competition associated with carrion. We hypothesize that the microbiome evolved social phenotypes, such as biofilms, that protect the bees from opportunistic pathogens present on carcasses, allowing them to overcome novel nutritional challenges. Whether specific microbes enabled diet shifts or diet shifts occurred first and microbial evolution followed requires further research to disentangle. Nonetheless, we find that necrophagous microbiomes, vertebrate and invertebrate alike, have functional commonalities regardless of their taxonomy.
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This content will become publicly available on May 16, 2026
Ultraconserved Elements Reveal the Relationship Between Facultative Keratinophagy and Synanthropic Evolution in Clothes Moths
ABSTRACT Synanthropic species live in close association with, or benefit from, humans. Despite their potential impacts to human health, little is known about the mechanisms driving synanthropic life‐history evolution, evolutionary forces shaping diet among synanthropes, or how these combined factors affect population dynamics and/or speciation. The Tineidae moth family contains several synanthropic species, including the globally distributed pest speciesTineola bissellellia, that contribute to the ~$1 billion worth of damage caused annually by keratinophagous synanthropes. Synanthropy among Tineidae is associated with a wide range of dietary strategies. While most tineids display obligate detritivory, synanthropic species are typically either facultatively or obligately keratinophagous. However, little is known about evolutionary relationships within Tineidae, hampering efforts to investigate the relationship between synanthropy and diet evolution. Here, to address this challenge, we extracted DNA from 39 tineid samples and two outgroups, including the closely relatedTineolaandTineagenera, and generated genome‐wide sequence data for thousands of ultraconserved elements (UCEs). Our phylogenetic analyses, using a concatenated maximum‐likelihood‐based approach, resulted in a well‐supported, fully resolved phylogeny that demonstrates synanthropy has evolved multiple times and is consistently associated with facultative and obligate keratinophagy. Bayesian divergence time estimation indicates Cretaceous divergence among deep‐branching tineid lineages, an ancestral origin of facultative keratinophagy, and a recent origin of the most economically important synanthropic pest,Tineola bissellellia,from within genusTinea. Taken together, our results suggest that a shift to facultative keratinophagy was a key evolutionary innovation that has fuelled the repeated evolution of synanthropic life histories among this deep‐diverging moth family.
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- Award ID(s):
- 2242864
- PAR ID:
- 10591006
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- ISSN:
- 0962-1083
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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