Using national crop and livestock production records from 1961–2003 and satellite-derived data on pasture greenness from 1982–2003 we show that the productivity of crops, livestock, and pastures in Africa is predictably associated with the El Niño Southern Oscillation and the North Atlantic Oscillation. The causal relations of these results are...
Human-induced changes in life-history traits have been observed for many harvested populations, with a component of those changes being attributed to an evolutionary (i.e., genetic) response. Most notably, fish stocks that experience high fishing mortality show a tendency to mature earlier and at a smaller size. Some have suggested that...
The objectives pursued by governments managing fisheries may include harvesting the fish stocks to maximize profits, to minimize the impact of harvesting on the marine ecosystem, or to secure jobs in the fishing industry. These objectives all depend on the composition of the fishing fleet as the various vessel types...