'Doomsday Glacier' is teetering even closer to disaster than scientists thought, new seafloor map shows

Scientists create coldest matter in the universe in a lab

Two new books about sharks reveal how and why we should conserve them

New research concludes that acts of generalized reciprocity—including initiating generosity and, upon being treated generously, paying it forward—are reduced when there is resource asymmetry between potential benefactors.