The microbiome impacts host hybridization and speciation

Abstract

Microbial symbiosis and speciation profoundly shape the composition of life’s biodiversity. Despite the enormous contributions of these two fields to the foundations of modern biology, there is a vast and exciting frontier ahead for research, literature, and conferences to address the neglected prospects of merging their study. Here, we survey and synthesize exemplar cases of how endosymbionts and microbial communities affect animal hybridization and vice versa. We conclude that though the number of case studies remain nascent, the wide-ranging types of animals, microbes, and isolation barriers impacted by hybridization will likely prove general and a major new phase of study that includes the microbiome as part of the functional whole contributing to reproductive isolation. Though microorganisms were proposed to impact animal speciation a century ago, the weight of the evidence supporting this view has now reached a tipping point.

First insight into oral microbiome diversity in Papua New Guineans reveals a specific regional signature

“…In recent years the field of host-associated microbes has greatly increased due to a desire to understand how the microbiome impacts a broad array of hosts, such as animals, plants and algae (Parfrey, Moreau, & Russell, 2018). Microbes have been shown to be involved in host immunity, digestion and nutrient scavenging activities, facilitate metabolism and cellular growth, regulate behavior, and release microbial toxins, among others (Miller, Westlake, Cross, Leigh, & Bordenstein, 2021). However, the first step in understanding host-microbiota dynamics is to identify the composition of the microbiome, and for that unique microbiomes across diverse host populations must be studied (Parfrey et al, 2018).…”

Research Progress of the Gut Microbiome in Hybrid Fish

“…Species are reproductively isolated groups composed of potentially interbreeding individuals, and hybrids can suffer from post-mating isolation barriers, such as sterility and/or unviability [ 173 ]. The composition and functional effects of animal microbiota are closely related to host evolution, and the survival rate and performance of microorganisms can be reduced when interspecific microbiota transplantation occurs between closely related and different host species pairs.…”

“…The composition and functional effects of animal microbiota are closely related to host evolution, and the survival rate and performance of microorganisms can be reduced when interspecific microbiota transplantation occurs between closely related and different host species pairs. The microbiome compositional relationships (i.e., beta diversity) reflect the evolutionary relationships of the host species [ 173 , 174 ]. Thus, natural selection can drive phylosymbiotic changes within the parental species, which may lead to the evolution of deleterious interactions between hybrids and their microbiomes [ 173 ].…”

“…The microbiome compositional relationships (i.e., beta diversity) reflect the evolutionary relationships of the host species [ 173 , 174 ]. Thus, natural selection can drive phylosymbiotic changes within the parental species, which may lead to the evolution of deleterious interactions between hybrids and their microbiomes [ 173 ].…”

Isolation, culture and characterization of Arsenophonus symbionts from two insect species reveal loss of infectious transmission and extended host range in the apicola-nasoniae group

“…Contrastingly, heritable microbes can also act as reproductive parasites, causing sex-ratio distortion and cytoplasmic incompatibility (9). The impact symbionts have on individual hosts – both beneficial and parasitic - cascades to ecological and evolutionary dynamics, for instance driving changes in the natural enemy-host dynamics (10), altering patterns of sexual selection (11), and potentiating host biodiversity over macroevolutionary timescales (12).…”