Local thermal extremes shape the nature of herbivore plasticity that controls plant communities

Prevailing views hold that species’ physiological plasticity may confer resilience to warming, but its importance varies across climatic gradients (e.g., latitude). Yet, along such gradients local species populations may experience fine-scale spatially heterogeneous variation in extreme temperatures and other ecological stressors. We show that at four Cool (mean diel maximum 29.83°C) and four Warm (mean diel maximum 31.51°C) sites, interspersed as a spatial mosaic throughout a 26,200 km2 area, local herbivore populations responded differently to stress from experimental warming (ambient, warmed) and predation (presence, absence).  Cool and Warm site herbivore populations utilized different combinations of behavioral and physiological plasticity to cope with the dual stressors that were contingent on local temperature extremes. These unique plastic responses had divergent cascading effects on the plant community. Our results suggest that paying attention to local population variatio..., Field experiment design
For each grasshopper population, we factorially crossed spider predation risk (present, absent) and experimental warming (warming, ambient) using experimental mesocosm cages in the field. Each cylindrical cage (0.25 m2 × 1.0 m H) was constructed using vinyl-coated garden wire fencing; the sides and tops of each cage were covered with insect screening. We deployed 20 cages (each separated by at least 1 m) within each field over naturally growing vegetation. We selected cage locations to ensure they all contained a similar initial composition of grass and Solidago, which was verified by measuring initial percent cover of grass and Solidago.
We created experimental warming treatments by wrapping the sides of assigned cages with translucent plastic sheeting (4 mm Film-Gard, Covalence Plastics, Minneapolis, MN, USA); the bottom 10 cm of the cages was left unwrapped to permit airflow. Experimental warming does not increase temperatures consistently over 24 hours: warmi..., , # Local thermal extremes shape the nature of herbivore plasticity that controls plant communities

[https://doi.org/10.5061/dryad.v15dv427d](https://doi.org/10.5061/dryad.v15dv427d)

## Description of the data and file structure

The dataset contains 12 comma separated value files which encompass all of the data used in the statistical analyses for this manuscript. These files consist of climate data, measures of grasshopper (*Melanoplus femurrubrum*) plasticity, and plant community biomass. The climate data consists of *in situ* temperature measurements and remotely sensed precipitation data used to (1) characterize sites, (2) determine the influence of experimental warming on thermal regimes, and (3) record weather during behavioral assays. The grasshopper plasticity data measures how experimental warming altered (1) grasshopper canopy height, (2) grasshopper respiration rates, and (3) grasshopper survival. The plant community impact data consists of measures of initial conditions and...,