Researchers have long been puzzled by two rapid and widespread changes in the abundance and distribution of North Pacific plankton and fish species that impacted the region's economically important salmon fisheries. Now, researchers suggest that longer, less frequent climate fluctuations may be contributing to abrupt and unexplained ecosystem shifts in the North Pacific.
A new study presents a novel approach for identifying vertebrate populations at risk of extinction by estimating the rate of genetic diversity loss, a measurement that could help researchers and conservationists better identify and rank species that are threatened or endangered.
Among birds, the line between species is often blurry. Some closely related species interbreed where their ranges overlap, producing hybrid offspring. In the coastal marshes of New England, this has been happening between the Saltmarsh Sparrow and Nelson's Sparrow. Research finds that appearance alone is not enough to identify these hybrid zone birds.