Mate preference and disease risk in Zootermopsis angusticollis (Isoptera: Termopsidae).
Termites face significant and chronic intranidal selection pressures from parasites and pathogens that colonize their nests. They also encounter microbes outside their nest while foraging and during dispersal of winged primary reproductives to establish new colonies. The latter run  the additional risk of becoming infected by a mating partner. Indeed, death of reproductives because of disease is a major cause of incipient colony failure and may favor prescreening prospective mates for signs of illness. To determine the role of disease on mate preference in termites, female  primary reproductives of the Pacific dampwood termite Zootermopsis angusticollis (Hagen) simultaneously were presented with reproductive males that were either healthy or exhibiting a progression of symptoms associated with infection by the entomopathogenic fungus Metarhizium anisopliae (Metchnikoff  Sorokin). We compared duration and frequency of female visits to healthy and infected males. In addition, we determined the physiological consequences for females exposed to fungal conidia, either directly or indirectly through their mate. Females showed no preference for healthy rather than  infected males. Moreover, only directly-exposed females experienced negative physiological effects, having a reduced chance of survival, gaining less weight, developing fewer functional ovarioles, and producing significantly fewer vitellogenic oocytes than controls. Although there are important  fitness-related costs of direct exposure, the lack of mate selection based on disease risk suggests that more imminent ecological pressures (e.g., predators, desiccation) override the need for a careful and time-consuming assessment of a potential mate's health.
Department of Biology, Northeastern University, 134 Mugar Life Sciences Bldg., 360 Huntington Ave., Boston, MA 02115-5000, USA. r.rosengaus@neu.edu
Rebeca B
RB
Rosengaus
Lady-Thelma
LT
James
Tamara R
TR
Hartke
Colin S
CS
Brent
D000818:Animals; D002140:California; D004198:Disease Susceptibility; D017753:Ecosystem; D005260:Female; D020049:Isoptera / Q000254:growth & development / Q000276:immunology / Q000382:microbiology* / Q000502:physiology*; D008297:Male; D052586:Mating Preference, Animal; D052981:Metarhizium / Q000502:physiology*; D012098:Reproduction; D046468:Sexual Development