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Metabolism provides a basis for using first principles of physics, chemistry, and biology to link the biology of individual organisms to the ecology of populations, communities, and ecosystems. Metabolic rate, the rate at which organisms take up, transform, and expend energy and materials, is the most fundamental biological rate. We have developed a(More)
The latitudinal gradient of increasing biodiversity from poles to equator is one of the most prominent but least understood features of life on Earth. Here we show that species diversity can be predicted from the biochemical kinetics of metabolism. We first demonstrate that the average energy flux of populations is temperature invariant. We then derive a(More)
Observations that rates of molecular evolution vary widely within and among lineages have cast doubts on the existence of a single "molecular clock." Differences in the timing of evolutionary events estimated from genetic and fossil evidence have raised further questions about the accuracy of molecular clocks. Here, we present a model of nucleotide(More)
The diversity of life is ultimately generated by evolution, and much attention has focused on the rapid evolution of ecological traits. Yet, the tendency for many ecological traits to instead remain similar over time [niche conservatism (NC)] has many consequences for the fundamental patterns and processes studied in ecology and conservation biology. Here,(More)
Ecosystem respiration is the biotic conversion of organic carbon to carbon dioxide by all of the organisms in an ecosystem, including both consumers and primary producers. Respiration exhibits an exponential temperature dependence at the subcellular and individual levels, but at the ecosystem level respiration can be modified by many variables including(More)
Understanding energy and material fluxes through ecosystems is central to many questions in global change biology and ecology. Ecosystem respiration is a critical component of the carbon cycle and might be important in regulating biosphere response to global climate change. Here we derive a general model of ecosystem respiration based on the kinetics of(More)
The size and metabolic rate of cells affect processes from the molecular to the organismal level. We present a quantitative, theoretical framework for studying relationships among cell volume, cellular metabolic rate, body size, and whole-organism metabolic rate that helps reveal the feedback between these levels of organization. We use this framework to(More)
The mechanisms responsible for latitudinal biodiversity gradients have fascinated and perplexed biologists since the time of Darwin. Ecological theory has yielded two general classes of mechanisms to account for variation in biodiversity: dispersal-assembly mechanisms that invoke differences in stochastic rates of speciation, extinction and dispersal; and(More)
A latitudinal gradient in biodiversity has existed since before the time of the dinosaurs, yet how and why this gradient arose remains unresolved. Here we review two major hypotheses for the origin of the latitudinal diversity gradient. The time and area hypothesis holds that tropical climates are older and historically larger, allowing more opportunity for(More)