predation, larvae, nutrition, mosquitoes, Aedes aegypti
Predation impacts development, behavior and morphology of prey species thereby shaping their abundances, distribution and community structure. Non-lethal threat of predation, specifically, can have a strong influence on prey lifehistory characteristics. While investigations often focus on the impact of predation threat on prey in isolation, tests of its interactive effects with food availability and resource competition on prey survival and fitness can improve understanding of costs, benefits and trade-offs of anti-predator strategies. This study, involving Aedes aegypti mosquitoes as a model organism, investigates both simple and interactive effects of predation threat during the larval stage on survival, size at and time to maturity, stored teneral reserves of glycogen, protein and lipid in adults, and adult longevity. Our results show that development times of mosquito larvae were increased (by 14.84% in males and by 97.63% in females), and size of eclosing adults decreased (by 62.30% in males and by 58.33% in females) when exposed to lowered nutrition and elevated intraspecific competition, but that predation had no detectable effect on these simple traits. Teneral reserves of glycogen, protein and lipid and adult longevity were positively correlated with adult body size. Non-lethal predation threat had significant interactive effects with nutrition and larval competition on teneral reserves in males and adult longevity in males and females. The sexes responded differently to conditions encountered as larvae, with the larval environment affecting development and adult characteristics more acutely for females than for males. The outcome of this study shows how threat of predation on juveniles can have long-lasting effects on adults that are likely to impact mosquito population dynamics and that may impact disease transmission.
This research was supported by: Fulbright-Nehru Doctoral Research Fellowship 2014-15 from the US-India Educational Foundation, New Delhi (India) and the Institute of International Education, New York (USA) to KC; 2015 Patel Grant sponsored by the Institute of International Education to KC; R.D.Wiegel Phi Sigma Research Grant from the School of Biological Sciences, Illinois State University all to KC; by National Institute of Health grant 1R15AI094322-01A1 to SAJ; and by National Centre for Biological Sciences, India support to SQ.
Chandrasegaran, Karthikeyan; Kandregula, Samyuktha Rao; Quader, Suhel; and Juliano, Steven A., "Context-dependent interactive effects of non-lethal predation on larvae impact adult longevity and body composition" (2018). Faculty Publications – Biological Sciences. 143.