Short-term exposure to predation affects body elemental composition, climbing speed and survival ability in Drosophila melanogaster.
Factors such as temperature, habitat, larval density, food availability and food quality substantially affect organismal development. In addition, risk of predation has a complex impact on the behavioural and morphological life history responses of prey. Responses to predation risk seem to be mediated by physiological stress, which is an adaptation for maintaining homeostasis and improving survivorship during life-threatening situations. We tested whether predator exposure during the larval phase of development has any influence on body elemental composition, energy reserves, body size, climbing speed and survival ability of adult Drosophila melanogaster. Fruit fly larvae were exposed to predation by jumping spiders (Phidippus apacheanus), and the percentage of carbon (C) and nitrogen (N) content, extracted lipids, escape response and survival were measured from predator-exposed and control adult flies. The results revealed predation as an important determinant of adult phenotype formation and survival ability. D. melanogaster reared together with spiders had a higher concentration of body N (but equal body C), a lower body mass and lipid reserves, a higher climbing speed and improved adult survival ability. The results suggest that the potential of predators to affect the development and the adult phenotype of D. melanogaster is high enough to use predators as a more natural stimulus in laboratory experiments when testing, for example, fruit fly memory and learning ability, or when comparing natural populations living under different predation pressures.
Department of Psychology, University of Tennessee, Knoxville, United States; Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia; Department of Risk Assessment and Epidemiology, Institute of Food Safety, Animal Health and Environment BIOR, Riga, Latvia.
Indrikis
I
Krams
Bredesen Center, Energy Science and Engineering, University of Tennessee , Knoxville , United States.
Sarah
S
Eichler Inwood
Centre for Ecology and Environmental Research, Vilnius University, Vilnius, Lithuania; Department of Biotechnology, Daugavpils University, Daugavpils, Latvia.
Giedrius
G
Trakimas
Department of Biotechnology, Daugavpils University , Daugavpils , Latvia.
Ronalds
R
Krams
Departments of Psychology and Ecology & Evolutionary Biology, University of Tennessee , Knoxville , TN , United States.
Gordon M
GM
Burghardt
Department of Plant Sciences, University of Tennessee , Knoxville , United States.
David M
DM
Butler
School of Psychology, University of Auckland, Auckland, New Zealand; English, Drama and Writing Studies, University of Auckland, Auckland, New Zealand.
Severi
S
Luoto
Department of Plant Protection, Estonian University of Life Science , Tartu , Estonia.
Tatjana
T
Krama
Body reserves; Drosophila melanogaster; Elemental composition; Fear ecology; Negative geotaxis; Spider predation; Stress; Survival