Non-consumptive effects of an ectoparasitic mite on a Drosophila host

  • Author / Creator
    Horn, Collin James
  • Parasite ecology has increasingly recognized that parasites have ecologically significant roles beyond infection. One mechanism by which parasites influence their communities outside infection is by imposing trade-offs on potential hosts. Non-consumptive effects (NCEs) are the negative impacts potential prey or hosts experience that may be driven by trade-offs between reproduction, feeding, dispersal, etc, and defence against natural enemies. In this thesis I investigated short and long term NCEs experienced by Drosophila nigrospiracula exposed, but not infected by, its natural ectoparasite Macrocheles subbadius. I also investigated how potential hosts vary in the NCEs they experienced based on sex and mating status. Flies varied in NCEs (physiological and behavioural) based on sex and mating status, at least in the short term. Moreover, individual female flies had reduced fecundity and survival during chronic mite exposure; however these changes may not scale up to population level effects based on current simulations. In the short term, mite resistance trades off with dispersal ability and reproduction. Thus there is a need to study how individual hosts and host populations compensate for NCEs and how this varies among different host groups. Additional research on parasite NCEs across different scales (ecological, generational) and fly lifespan may show the lifetime impacts of NCEs are larger than suggested here. This thesis contributes to our attempts to extend “the ecology of fear” to host-parasite interactions.

  • Subjects / Keywords
  • Graduation date
    Fall 2022
  • Type of Item
  • Degree
    Doctor of Philosophy
  • DOI
  • License
    This thesis is made available by the University of Alberta Library with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.