Science

A pedestrian walk past a building housing the Warren Alpert Medical School of Brown University, Wednesday, Jan. 30, 2019, in Providence, R.I. On Tuesday a prominent physicians' group asked the U.S. Department of Agriculture to investigate the school, arguing that it is violating the law by using live pigs for training in emergency medicine. (AP Photo/Jennifer McDermott)

In this Tuesday, Jan, 29, 2019, photo. Mount Merapi spews volcanic material as it erupts as seen from Cangkringan, Yogyakarta, Indonesia. Indonesia's most volatile volcano unleashed a 1,400 meters (4,600 feet) dark red volcanic material 1,400 meters (1,500 yards) down the slopes. (AP Photo/Slamet Riyadi)

FILE - This June 30, 2017 remote camera image released by the U.S. Forest Service shows a female gray wolf and her mate with a pup born in 2017 in the wilds of Lassen National Forest in Northern California, A California judge has upheld protection for gray wolves under the state's Endangered Species Act, rejecting a challenge from ranchers and farmers. The judge in San Diego ruled Monday, Jan. 28, 2019 that California was right when it listed wolves as endangered in 2014. (U.S. Forest Service via AP, File)

FILE - This Feb. 6, 2015, file photo, shows a measles, mumps and rubella vaccine on a countertop at a pediatrics clinic in Greenbrae, Calif. A measles outbreak near Portland has sickened dozens of people in Oregon and Washington, with several more cases suspected, and public health officials scrambling to contain the virus say low vaccination rates are making the situation worse. Clark County Public Health said Sunday, Jan. 28, 2019, that the majority of the cases involve children younger than 10. (AP Photo/Eric Risberg, File)

People walk through a snowstorm in downtown Jackson, Mich., Monday, Jan. 28, 2019. (J. Scott Park/Jackson Citizen Patriot via AP)

FILE - In this July 19, 2007 file photo, Nobel Prize-winning scientist Craig Mello, front, acknowledges applause from members of the Massachusetts House and Senate on the floor of the House Chamber at the Statehouse in Boston. Emails obtained by The Associated Press show Chinese scientist He Jiankui told Mello about the gene-edited babies in April 2018, months before the claim became public. Mello objected to the experiment and remained an adviser to He's biotech company for eight more months before resigning. (AP Photo/Steven Senne, File)

Toshiba Corp.'s energy systems unit group manager Jun Suzuki shows a remote-controlled melted fuel probe device at its facility in Yokohama, near Tokyo, Monday, Jan. 28, 2019. Toshiba unveiled the device carrying tongs that comes out of a long telescopic pipe for an internal probe in one of three damaged reactor chambers at Japan’s tsunami-hit Fukushima nuclear plant - this time to touch chunks of melted fuel. (AP Photo/Mari Yamaguchi)

FILE - In this Nov. 15, 2017 file photo, Haider, left, and Abdullah carry belongings they collected from their damaged house to wash before returning to live in the Old City of Mosul, Iraq. For centuries, residents of Mosul have spoken a unique form of Arabic enriched by the Iraqi city’s long history as a crossroads of civilization, a singsong dialect that many now fear will die out after years of war and displacement. (AP Photo/Felipe Dana, File)