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Phenotypically plastic responses to predation risk are temperature dependent

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Predicting how organisms respond to climate change requires that we understand the temperature dependence of fitness in relevant ecological contexts (e.g., with or without predation risk). Predation risk often induces changes to life history traits that are themselves temperature dependent. We explore how perceived predation risk and temperature interact to determine fitness (indicated by the intrinsic rate of increase, r) through changes to its underlying components (net reproductive rate, generation time, and survival) in Daphnia magna. We exposed Daphnia to predation cues from dragonfly naiads early, late, or throughout their ontogeny. Predation risk increased r differentially across temperatures and depending on the timing of exposure to predation cues. The timing of predation risk likewise altered the temperature-dependent response of T and R0. Daphnia at hotter temperatures responded to predation risk by increasing r through a combination of increased R0 and decreased T that together countered an increase in mortality rate. However, only D. magna that experienced predation cues early in ontogeny showed elevated r at colder temperatures. These results highlight the fact that phenotypically plastic responses of life history traits to predation risk can be strongly temperature dependent.
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Oecologia (2019) 191:709–719
https://doi.org/10.1007/s00442-019-04523-9
GLOBAL CHANGE ECOLOGY – ORIGINAL RESEARCH
Phenotypically plastic responses topredation risk are temperature
dependent
ThomasM.Luhring1,2 · JannaM.Vavra1· ClaytonE.Cressler1· JohnP.DeLong1
Received: 7 September 2018 / Accepted: 30 September 2019 / Published online: 10 October 2019
© Springer-Verlag GmbH Germany, part of Springer Nature 2019
Abstract
Predicting how organisms respond to climate change requires that we understand the temperature dependence of fitness in
relevant ecological contexts (e.g., with or without predation risk). Predation risk often induces changes to life history traits
that are themselves temperature dependent. We explore how perceived predation risk and temperature interact to determine
fitness (indicated by the intrinsic rate of increase, r) through changes to its underlying components (net reproductive rate,
generation time, and survival) in Daphnia magna. We exposed Daphnia to predation cues from dragonfly naiads early,
late, or throughout their ontogeny. Predation risk increased r differentially across temperatures and depending on the tim-
ing of exposure to predation cues. The timing of predation risk likewise altered the temperature-dependent response of T
and R0. Daphnia at hotter temperatures responded to predation risk by increasing r through a combination of increased R0
and decreased T that together countered an increase in mortality rate. However, only D. magna that experienced predation
cues early in ontogeny showed elevated r at colder temperatures. These results highlight the fact that phenotypically plastic
responses of life history traits to predation risk can be strongly temperature dependent.
Keywords Climate change· Fecundity· Life history· Mortality· Reproduction· Survivorship
Introduction
Global climate change is leaving an indelible mark on the
ecology of organisms worldwide (Walther etal. 2002;
Parmesan 2006; Poloczanska etal. 2013). Organisms can
respond to climate change through rapid evolutionary and/
or developmental changes in morphology, behavior, and life
history (Reale etal. 2003; Knies etal. 2006, 2009; Charman-
tier etal. 2008; Angilletta etal. 2010; Anderson etal. 2012;
Charmantier and Gienapp 2014; Tseng and O’Connor 2015;
Seebacher etal. 2015; Padfield etal. 2016; Schaum etal.
2017). Furthermore, changing thermal regimes associated
with climate change influence virtually all aspects of natural
systems, because biological processes are dominated by the
effects of temperature (Ernest etal. 2003; Brown etal. 2004;
Kerkhoff etal. 2005; Kingsolver 2009; DeLong etal. 2017).
While the temperature dependence of fitness is of interest
for projecting the effects of climate change (Deutsch etal.
2008; Vasseur etal. 2014; Sinclair etal. 2016), the traits
that determine fitness occur within the context of natural
food webs and are simultaneously altered and constrained
by temperature and other factors (e.g., predation, allocation
trade-offs) (Luhring etal. 2018).
Predation and predation risk strongly influence prey evo-
lution, development, morphology, behavior, and life history
(Reznick and Endler 1982; Lima and Dill 1990; Stibor 1992;
Van Buskirk and Schmidt 2000; Benard 2004; Lind and
Cresswell 2005; Grigaltchik etal. 2012, 2016; Seebacher
and Grigaltchik 2015; Tseng and O’Connor 2015; Luhring
etal. 2016). Furthermore, predators shape prey demography
and dynamics through both the lethal effects of predation
and the effects of predation risk on prey behavior and phe-
notypes (Pangle etal. 2007; Creel and Christianson 2008;
Communicated by Scott D Peacor.
Electronic supplementary material The online version of this
article (https ://doi.org/10.1007/s0044 2-019-04523 -9) contains
supplementary material, which is available to authorized users.
* Thomas M. Luhring
tomluhring@gmail.com
1 School ofBiological Sciences, University ofNebraska-
Lincoln, 410 Manter Hall, Lincoln, NE68588, USA
2 Present Address: Department ofBiological Sciences, Wichita
State University, 1845 Fairmount Street, Wichita, KS67260,
USA
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... How biotic stressors such as predation risk can alter the physiology of prey species and further modulate their sensitivity to warming remain a major gap of knowledge. Few studies have investigated the effect of predator cues on zooplankton under elevated temperatures (e.g., Luhring et al., 2019;Meyer et al., 2017;Tseng and O'Connor, 2015). In freshwater ecosystems, Meyer et al. (2017) showed that effects of predators (Cyclops kolensis) on the abundance of prey animals (Gastropus stylifer and Keratella cochlearis and copepod nauplii) are independent of temperatures. ...
... FPC was thaw before using. Effects of predator cues on prey animals remain after freezing (Luhring et al., 2019). ...
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