Metacommunity theory for transmission of heritable symbionts within insect communities

Abstract

Microbial organisms are ubiquitous in nature and often form communities closely associated with their host, referred to as the microbiome. The microbiome has strong influence on species interactions, but microbiome studies rarely take interactions between hosts into account, and network interaction studies rarely consider microbiomes. Here, we propose to use metacommunity theory as a framework to unify research on microbiomes and host communities by considering host insects and their microbes as discretely defined “communities of communities” linked by dispersal (transmission) through biotic interactions. We provide an overview of the effects of heritable symbiotic bacteria on their insect hosts and how those effects subsequently influence host interactions, thereby altering the host community. We suggest multiple scenarios for integrating the microbiome into metacommunity ecology and demonstrate ways in which to employ and parameterize models of symbiont transmission to quantitatively assess metacommunity processes in host‐associated microbial systems. Successfully incorporating microbiota into community‐level studies is a crucial step for understanding the importance of the microbiome to host species and their interactions.

Ontogeny, species identity, and environment dominate microbiome dynamics in wild populations of kissing bugs (Triatominae)

“…Hematophagous (blood-feeding) organisms are broadly affected by their associated microbial communities (referred to as the “microbiome”). Microbiome diversity, composition, and function directly influence various fundamental aspects of host biology, such as immunity, thermal tolerance, and digestion [ 11 – 13 ]. Nutritionally, blood is rich in proteins and salt, lacks vitamins, and its breakdown releases toxic amounts of haem and urea [ 14 , 15 ].…”

Ontogeny, species identity and environment dominate microbiome dynamics in wild populations of kissing bugs (Triatominae)

“…Hematophagous (blood-feeding) organisms are broadly affected by their associated microbial communities (referred to as the 'microbiome'). Microbiome diversity, composition, and function directly influence various fundamental aspects of host biology, such as immunity, thermal tolerance, and digestion [11][12][13]. Nutritionally, blood is rich in proteins and salt, lacks vitamins, and its breakdown releases toxic amounts of haem and urea [14,15].…”

Spiroplasma Infection among Ixodid Ticks Exhibits Species Dependence and Suggests a Vertical Pattern of Transmission

“…The presence of these alleles resulted in the high overall infection rates in I. ovatus and H. kitaokai . These Spiroplasma alleles may have adapted to the tick environment, which is important for symbionts [ 45 ]. The transmission of symbionts occurs mainly through the vertical or horizontal route.…”

“…Vertical transmission involves the dispersal of symbionts and occurs primarily from the mother to offspring. Horizontal transmission occurs via host-to-host contact and acquisition from the environment [ 45 ]. The high infection rates observed in I. ovatus and H. kitaokai suggest the vertical transmission of Spiroplasma in these tick species.…”

“…Symbionts can positively affect the nutrition, reproduction, and defence of their hosts. These positive effects may promote the coexistence or coevolution of symbionts and their hosts [ 45 ]. Therefore, it is of particular interest to investigate whether Spiroplasma affects tick fitness, as it may help understand the close association between Spiroplasma and ticks.…”