Science News writer Nathan Seppa talks with physicians about people opting out of vaccinations.

New estimates suggest the mammals’ feeding habits help take in carbon.

Some were pets whose bodies and appetites apparently got too big for their owners to support. Most are probably descendants of released pets. Today, thousands of really big non-native snakes — we’re talking boa constrictors, anacondas and pythons — slither wild in southern Florida. And there’s nothing holding them in the Sunshine State. Which is why a report that was released today contends they pose moderate to high ecological threats to states on three U.S. coasts. Indeed, the homelands of these snakes share climatic features with large portions of the United States — territory currently inhabited by some 120 million Americans. Based on comparisons of the temperatures, rainfall and land cover found in the snakes’ native range, it’s possible that these slithering behemoths could stake claims to territory as far north as coastal Delaware and Oregon.

A new technique allows scientists to map the 3-D structure of the entire human genome.