Whales dine with their friends of the same species

For a few weeks in early fall, Georges Bank — a vast North Atlantic fishery off the coast of Cape Cod — teems with billions of herring that take over the region to spawn. The seasonal arrival of the herring also attracts predators to the shallow banks, including many species of whales.Now researchers from MIT, Northeastern University, the Institute of Marine Research in Norway, and the National Oceanic and Atmospheric Administration, have found that as multiple species of whales feast on herring, they tend to stick with their own kind, establishing species-specific feeding centers along the 150-mile length of Georges Bank. The team’s results are published today in the journal Nature.

The economic benefits of mercury reductions

Mercury pollution is a global problem with local consequences: Emissions from coal-fired power plants and other sources travel around the world through the atmosphere, eventually settling in oceans and waterways, where the pollutant gradually accumulates in fish. Consumption of mercury-contaminated seafood leads to increased risk for cardiovascular disease and cognitive impairments.In the past several years, a global treaty and a domestic policy have been put in place to curb mercury emissions. But how will such policies directly benefit the U.S.? 

Something not to worry about, the Earth's magnetic field flipping

The intensity of Earth’s geomagnetic field has been dropping for the past 200 years, at a rate that some scientists suspect may cause the field to bottom out in 2,000 years, temporarily leaving the planet unprotected against damaging charged particles from the sun. This drop in intensity is associated with periodic geomagnetic field reversals, in which the Earth’s North and South magnetic poles flip polarity, and it could last for several thousand years before returning to a stable, shielding intensity.With a weakened geomagnetic field, increased solar radiation might damage electronics — from individual pacemakers to entire power grids — and could induce genetic mutations. A reversal may also affect the navigation of animals that use Earth’s magnetic field as an internal compass.