Selection history alters fitness across ecological interactions in a fly-parasitoid system
- 1National Centre for Biological Sciences (NCBS-TIFR)
Abstract
Species interactions shape ecological dynamics, but adaptation to one interaction can trade off with others. Experiments that measure such evolved fitness changes across multiple interactions remain rare. We used experimental evolution to test whether recent selection under one ecological interaction changes fitness under other interactions in a fly-parasitoid system. We evolved a genetically diverse Drosophila melanogaster population for 15-17 generations under three regimes: benign conditions (control), high intraspecific competition, and infection by the parasitoid wasp Leptopilina boulardi. We then measured fly fitness (egg-to-adult survival and subsequent reproduction) under benign conditions, high intraspecific competition, and infection by three other parasitoid species and an additional conspecific L. boulardi strain. Selection history strongly influenced fitness across interactions. Populations maintained under high larval density showed reduced survival under infection by L. boulardi and L. victoriae, indicating a trade-off between past selection for competition and defence against some parasitoids. Populations evolved under parasitoid infection by L. boulardi showed increased resistance to a conspecific strain but reduced fitness when infected by another species, L. heterotoma. Our results show that rapid evolution in response to a single interaction can reshape multiple ecological interactions through fitness trade-offs, highlighting how recent evolutionary history may influence community dynamics and invasion susceptibility.
Related
- Ecological and genomic insights into leafhopper-parasitoid interactions in Canadian agroecosystems under a changing climate
- Density-Dependence and agricultural intensity affect host-parasite-parasitoid interactions in a bird-insect trophic system
- Tritrophic Interactions and Parasitoid Community Structure of Gall‐Inducing Herbivores in Arid Desert Ecosystems of Northern Xinjiang, China
- Revealing parasitoid-pest interactions using multi-marker metabarcoding: a nationwide assessment of parasitism in cabbage stem flea beetle larvae
- Mean fitness is maximized in small populations under stabilizing selection on highly polygenic traits
BibTeX
@misc{kumar2026selection,
title = {{Selection history alters fitness across ecological interactions in a fly-parasitoid system}},
author = {V. Ravi Kumar and J. Esteves and V. Montbel and S. Rasouli-Dogaheh and V. Fedorchenko and J. Hrcek},
howpublished = {bioRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.20.752945},
url = {https://www.biorxiv.org/content/10.64898/2026.09.20.752945v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Selection history alters fitness across ecological interactions in a fly-parasitoid system
AU - V. Ravi Kumar
AU - J. Esteves
AU - V. Montbel
AU - S. Rasouli-Dogaheh
AU - V. Fedorchenko
AU - J. Hrcek
PY - 2026
DA - 2026/09/20
PB - bioRxiv
DO - 10.64898/2026.09.20.752945
UR - https://www.biorxiv.org/content/10.64898/2026.09.20.752945v1
AB - Species interactions shape ecological dynamics, but adaptation to one interaction can trade off with others. Experiments that measure such evolved fitness changes across multiple interactions remain rare. We used experimental evolution to test whether recent selection under one ecological interaction changes fitness under other interactions in a fly-parasitoid system. We evolved a genetically diverse Drosophila melanogaster population for 15-17 generations under three regimes: benign conditions (control), high intraspecific competition, and infection by the parasitoid wasp Leptopilina boulardi. We then measured fly fitness (egg-to-adult survival and subsequent reproduction) under benign conditions, high intraspecific competition, and infection by three other parasitoid species and an additional conspecific L. boulardi strain. Selection history strongly influenced fitness across interactions. Populations maintained under high larval density showed reduced survival under infection by L. boulardi and L. victoriae, indicating a trade-off between past selection for competition and defence against some parasitoids. Populations evolved under parasitoid infection by L. boulardi showed increased resistance to a conspecific strain but reduced fitness when infected by another species, L. heterotoma. Our results show that rapid evolution in response to a single interaction can reshape multiple ecological interactions through fitness trade-offs, highlighting how recent evolutionary history may influence community dynamics and invasion susceptibility.
ER -