Cloacal microbiomes of sympatric and allopatric Sceloporus lizards vary with environment and host relatedness

Abstract

Animals and their microbiomes exert reciprocal influence; the host’s environment, physiology, and phylogeny can impact the composition of the microbiome, while the microbes present can affect host behavior, health, and fitness. While some microbiomes are highly malleable, specialized microbiomes that provide important functions can be more robust to environmental perturbations. Recent evidence suggests Sceloporus virgatus has one such specialized microbiome, which functions to protect eggs from fungal pathogens during incubation. Here, we examine the cloacal microbiome of three different Sceloporus species (spiny lizards; Family Phrynosomatidae)–Sceloporus virgatus, Sceloporus jarrovii, and Sceloporus occidentalis. We compare two species with different reproductive modes (oviparous vs. viviparous) living in sympatry: S. virgatus and S. jarrovii. We compare sister species living in similar habitats (riparian oak-pine woodlands) but different latitudes: S. virgatus and S. occidentalis. And, we compare three populations of one species (S. occidentalis) living in different habitat types: beach, low elevation forest, and the riparian woodland. We found differences in beta diversity metrics between all three comparisons, although those differences were more extreme between animals in different environments, even though those populations were more closely related. Similarly, alpha diversity varied among the S. occidentalis populations and between S. occidentalis and S. virgatus, but not between sympatric S. virgatus and S. jarrovii. Despite these differences, all three species and all three populations of S. occcidentalis had the same dominant taxon, Enterobacteriaceae. The majority of the variation between groups was in low abundance taxa and at the ASV level; these taxa are responsive to habitat differences, geographic distance, and host relatedness. Uncovering what factors influence the composition of wild microbiomes is important to understanding the ecology and evolution of the host animals, and can lead to more detailed exploration of the function of particular microbes and the community as a whole.

Seasonal dietary changes relate to gut microbiota composition depending on the host species but do not correlate with gut microbiota diversity in arthropod‐eating lizards

“…While several studies attribute variation in gut microbiota composition to dietary shifts, most of them do not integrate dietary data in their analysis (see Bodawatta et al., 2022; Fan et al., 2022; Gao et al., 2023; Guo et al., 2021 for a few exceptions), limiting their conclusion about the influence of diet on gut microbiota variation. Importantly, seasonal variation in gut microbiota composition and its relationship with dietary changes may differ among lizard species (Gao et al., 2023), since life history features such as body size, reproductive season and modes (Bunker et al., 2022; Bunker & Weiss, 2022), feeding habits (Lankau et al., 2012; Vasconcelos et al., 2023) and geographical distribution (Härer et al., 2023) may affect both dietary and gut microbiota dynamics. Moreover, gut microbiota composition may be greatly affected by phylogenetic relatedness between vertebrate hosts (i.e.…”