Table 4.

Behavioural effects of infection with vertically acquired, endosymbiotic bacteria in arthropod hosts.

Behaviour	Effects	Symbionts		Host species (reference)
Reproductive
Female mating behaviour	Pre-mating isolation via selective mate avoidance, i.e., avoiding mates harboring another, incompatible symbiont variant.	Wolbachia		Drosophila paulistorum [71]
“	Females of thelytokous host strain inseminated less often than arrhenotokous (sexual) females.	Wolbachia		Apoanagyrus diversicornis [55]
“	Reproductive barrier between antibiotic-induced males and females due to nonreceptivity of females.	Unknown, but not Wolbachia		Galeopsomyia fausta [91]
Female mating behaviour (and anatomy)	Females reluctant to mate and also have ananatomical alteration: major spermathecal muscle absent	Wolbachia		Muscidifurax uniraptor [53]
Mate choice	Assortative mating dependent on genotype, infection status and combination.	Wolbachia		Drosophila melanogaster [92]
“	Males prefer real females to feminized genetic males	Wolbachia		Armadillidum vulgare [93]
“	Uninfected females prefer uninfected males	Wolbachia		Tetranychus urticae [21]
Male-male competition	Infected males are more competitive (more likely to mate with tester female when in direct competition)	Wolbachia		Drosophila melanogaster [73]
Male mating rate	Infected males mate more than uninfected counterparts	Wolbachia		Drosophila melanogaster & D. simulans [94]
“	Male ability to mate multiply higher in species harbouring feminizing symbiont	Wolbachia		Comparative analysis including 7 isopod species, five with feminizing versus two with CI-inducing Wolbachia symbionts [95]
Male fertility	Infected males do not produce mature sperm	Wolbachia		Muscidifurax uniraptor [53]
Aggregating/Lekking	Sex role reversal: females aggregate on hilltops to attract rare males	Wolbachia		Acraea encedon [22]
Female post-copulatory behaviour	Influence on offspring sex ratio via alteration of female post-copulatory position	Wolbachia		Pityohyphantes phrygianus [96]
Oviposition	Infected females aggregate offspring	Wolbachia		Tetranychus urticae [21]
“		Wolbachia		Encarsia hispida [97]
“	Cured females accept one host type at the same rate as control females but parasitized significantly fewer of the other host type.	Cardinium		Encarsia pergandiella [58]
Oviposition substrate preference	Uninfected flies preferentially lay eggs on wheat substrate, whereas infected flies do not exert apparent preference for a particular substrate		Wolbachia	Drosophila melanogaster [72]
Oviposition choice	Infection affects host choice (i.e., number of eggs laid in particular host type)		Cardinium	Encarsia pergandiella [98]
Non-reproductive
Larval competitive ability	Offspring of infected females are more competitive		Wolbachia	Drosophila melanogaster [20]
Dispersal	Infected females are less likely to adopt long-range dispersal behaviour (ballooning)		Rickettsia	Erigone atra [19]