1. Many insects host secondary bacterial symbionts that are known to have wide‐ranging
effects on their hosts, from host‐plant use to resistance against natural enemies. This has …

Highlights•Hamiltonella defensa is a bacterial symbiont protecting aphids against
parasitoids.•APSE viruses infect H. defensa and play key roles in the defensive …

Human bodies house trillions of symbiotic microorganisms. The genes in this human
microbiome outnumber human genes by 100 to 1, and their study is providing profound …

Symbiotic microbes have become increasingly recognized to mediate interactions between
natural enemies and their hosts. The ecologies of these symbioses, however, are poorly …

The microbiome can significantly impact host phenotypes and serve as an additional source
of heritable genetic variation. While patterns across eukaryotes are consistent with a role for …

Ecologically important traits of insects are often affected by facultative bacterial
endosymbionts. This is best studied in the pea aphid Acyrthosiphon pisum, which is …

Maternally transmitted associations between endosymbiotic bacteria and insects are diverse
and widespread in nature. Owing to imperfect vertical transmission, many heritable microbes …

Highlights•Multiple strains of the heritable bacterium, Spiroplasma, protect insects against
infection by natural enemies.•Defensive capabilities are broad, impacting parasitic …

Heritable symbionts are common in insects with many contributing to host defence.
Hamiltonella defensa is a facultative, bacterial symbiont of the pea aphid, Acyrthosiphon …

The discipline of molecular ecology has undergone enormous changes since the journal
bearing its name was launched approximately two decades ago. The field has seen great …