Data from: Metabolic theory and the temperature-size rule explain the temperature dependence of population carrying capacity

The temperature dependence of highly conserved subcellular metabolic
systems affects ecological patterns and processes across scales, from
organisms to ecosystems. Population density at carrying capacity plays an
important role in evolutionary processes, biodiversity and ecosystem
function, yet how it varies with temperature dependent metabolism remains
unclear. Though the exponential effect of temperature on intrinsic
population growth rate, r, is well known, we still lack clear evidence
that population density at carrying capacity, K, declines with increasing
per-capita metabolic rate, as is often assumed in the metabolic theory of
ecology (MTE). We experimentally tested whether temperature effects on
photosynthesis propagate directly to population carrying capacity in a
model species, the mobile phytoplankton Tetraselmis tetrahele. After
maintaining populations at constant resource supply and temperatures (6
levels) for 43 days, we found that density declined with increasing
temperature in a manner quantitatively consistent with predictions when
models included temperature-dependent metabolic rates and
temperature-associated body size shifts. Our results demonstrate that
warming reduces carrying capacity, and that temperature effects on body
size and metabolic rate interact to determine how temperature affects
population dynamics. These findings bolster efforts to relate metabolic
temperature dependence to population and ecosystem patterns via MTE.