Many households in developing countries rely on renewable natural resources as their main source of energy. Collecting and burning firewood requires a considerable amount of time, has negative health consequences, and can cause deforestation and depletion of local resources if forests are not...

Several highly cited papers suggest that commercial fishing is altering marine ecosystems by “fishing down the food chain”. Recent evidence calls into question the generality of the original findings, but the papers all raise the question: what mechanisms lie behind exploitation patterns in...