title: Experimental evidence for within- and cross-seasonal effects of fear on survival and reproduction.
abstract: Fear of predation can have non-lethal effects on individuals within a season but whether, and to what extent, these effects carry over into subsequent seasons is not known. Using a replicated seasonal population of the common fruit fly, Drosophila melanogaster, we examined both within- and cross-seasonal effects of fear on survival and reproductive output. Compared to controls, flies exposed to the scent of mantid (Tenodera sinensis) predators in the non-breeding season had 64% higher mortality, and lost 60% more mass by the end of the non-breeding season and, in the subsequent breeding season, produced 20% fewer offspring that weighed 9% less at maturity. Flies exposed to the scent of mantids in the breeding season did not produce fewer offspring, but their offspring developed faster and weighed less as adults compared to the controls. Our results demonstrate how effects of fear can be manifested both within and across seasons and emphasize the importance of understanding how events throughout the annual cycle influence individual success of animals living in seasonal environments.
authors.affiliation: Department of Integrative Biology, University of Guelph, Guelph, Canada, N1G 2W1.|Department of Natural Resource Sciences, McGill University, Ste Anne-de-Bellevue, Canada, H9X 3V9.
authors.forename: Kyle H
authors.initials: KH
authors.lastname: Elliott
authors.affiliation: Department of Integrative Biology, University of Guelph, Guelph, Canada, N1G 2W1.
authors.forename: Gustavo S
authors.initials: GS
authors.lastname: Betini
authors.affiliation: Department of Biology, McMaster University, Hamilton, Canada, L8S 4K1.
authors.forename: Ian
authors.initials: I
authors.lastname: Dworkin
authors.affiliation: Department of Integrative Biology, University of Guelph, Guelph, Canada, N1G 2W1.
authors.forename: D Ryan
authors.initials: DR
authors.lastname: Norris
mesh_terms: D000818:Animals; D004331:Drosophila melanogaster / Q000254:growth & development / Q000502:physiology*; D005239:Fear; D005260:Female; D020387:Food Chain; D007814:Larva / Q000254:growth & development / Q000502:physiology; D008136:Longevity; D008297:Male; D020050:Mantodea / Q000502:physiology*; D009812:Odorants / Q000032:analysis*; D012098:Reproduction; D012621:Seasons
keywords: Drosophila melanogaster; carry-over effects; non-consumptive effects; seasonality; top-down effects