Many bacterial and archaeal lineages have a history of extensive and ongoing horizontal
gene transfer and loss, as evidenced by the large differences in genome content even …

Comparisons of closely related microorganisms have shown that individual genomes can be
highly diverse in terms of gene content. In this Review, we discuss several studies showing …

Microbes drive most ecosystems and are modulated by viruses that impact their lifespan,
gene flow, and metabolic outputs. However, ecosystem-level impacts of viral community …

DNA viruses are increasingly recognized as influencing marine microbes and microbe-
mediated biogeochemical cycling. However, little is known about global marine RNA virus …

Extensive genomic diversity within coexisting members of a microbial species has been
revealed through selected cultured isolates and metagenomic assemblies. Yet, the cell-by …

Geothermal springs are model ecosystems to investigate microbial biogeography as they
represent discrete, relatively homogenous habitats, are distributed across multiple …

Multiple models describe the formation and evolution of distinct microbial phylogenetic
groups. These evolutionary models make different predictions regarding how adaptive …

Longstanding questions relate to the existence of naturally distinct bacterial species and
genetic approaches to distinguish them. Bacterial genomes in public databases form distinct …

Niches are spaces for the biological units of selection, from cells to complex communities. In
a broad sense,“species” are biological units of individuation. Niches do not exist without …

Microorganisms are the primary engines of biogeochemical processes and foundational to
the provisioning of ecosystem services to human society. Free‐living microbial communities …