Warming strengthens food web effects of predator phenotypic variation
Data files
Jun 26, 2025 version files 14.52 KB
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README.md
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Salo_et_al_plate_phenotypes.csv
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Salo_et_al_predation.csv
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Salo_et_al_stomach_contents.csv
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Abstract
Intraspecific variation modifies ecological processes and ecosystem functioning. Still, we know relatively little of how the nature and strength of ecosystem effects caused by intraspecific variation may interact with climate change.
We conducted a mesocosm experiment to test if, and to what extent, ocean warming modifies the ecological impacts of intraspecific variation in a predatory fish. The mesocosms consisted of a simplified coastal food web with threespine stickleback (Gasterosteus aculeatus) as the top predator, from a population where two stickleback phenotypes with either complete or incomplete lateral armour plating coexist and display differentiated predation behavior: The completely plated phenotype often feeds more on invertebrate herbivores compared to the incompletely plated phenotype.
Presence of stickleback reduced biomass of arthropod shredders (crustaceans, insect larvae). Warming (+4 °C) strengthened this predation, releasing benthic primary producers (diatoms) from top-down control, causing a trophic cascade. This trophic cascade was attributed to one of the plate phenotypes: the completely plated stickleback increased their predation on shredders under warming, while the incompletely plated stickleback instead decreased their predation. Diatom biomass responded accordingly: warming increased diatom biomass in the presence of completely plated stickleback but not when incompletely plated stickleback were present.
Our results suggest that different plate phenotypes of threespine stickleback differentially affect lower trophic levels, and that warming may exacerbate these cascading effects. These trait-dependent effects on trophic cascades highlight the consequences of intraspecific variation on ecosystem functioning.
Dataset DOI: https://doi.org/10.5061/dryad.kprr4xhhn
Salo_et_al_predation.csv
Salo_et_al_plate_phenotypes.csv
Salo_et_al_stomach_contents.csv
Contact information: tiina.salo@helsinki.fi
Data for Salo_et_al_predation.csv include:
temperature: temperature treatment in the study (ambient, high)
predation: presence or absence of top predators in the mesocosm (fish, no fish)
plate_phenotypes: three-spine stickleback plate phenotype (completely plated, incompletely plated, both, no_fish)
waterbath: waterbath id for nested analyses
shredder_biomass: the biomass (g dw) of shredders in the mesocosm
shredder_survival: the survival of shredders in the mesocosm
shredder_recruitment: the recruitment of shredders to the mesocosm
gastropod_biomass: the biomass (g dw) of gastropods in the mesocosm
theodoxus_eggs: the biomass (g dw) of Theodoxus fluviatilis eggs in the mesocosm
diatom_biomass: the biomass (g dw) of diatoms in the mesocosm
epiphyte_biomass: the biomass (g dw) epiphytic macroalgae in the mesocosm
turbidity: turbidity in the mesocosm
Data for Salo_et_al_plate_phenotypes.csv include:
temperature: temperature treatment in the study (ambient, high)
plate_phenotypes: three-spine stickleback plate phenotype (completely plated, incompletely plated, both, none)
waterbath: waterbath id for nested analyses
shredder_biomass: the biomass (g dw) of shredders in the mesocosm
shredder_survival: the survival of shredders in the mesocosm
shredder_recruitment: the recruitment of shredders to the mesocosm
gastropod_biomass: the biomass (g dw) of gastropods in the mesocosm
theodoxus_eggs: the biomass (g dw) of Theodoxus fluviatilis eggs in the mesocosm
diatom_biomass: the biomass (g dw) of diatoms in the mesocosm
epiphyte_biomass: the biomass (g dw) epiphytic macroalgae in the mesocosm
turbidity: turbidity in the mesocosm
Data for Salo_et_al_stomach contents.csv include:
temperature: temperature treatment in the study (ambient, high)
phenotype_teatment: three-spine stickleback plate phenotypes in the mesocosm (completely plated, incompletely plated, both)
plate_phenotype: plate phenotype of the fish (completely plated, incompletely plated)
mesocosm_code: mesocosm id for any nasted analyses
waterbath: waterbath id for any nested analyses
shredders: biomass (g dw) of shredders in the stomach