In this Thursday, April 14, 2016, photo, renter Nicole Caverlyat gets settled at her home in the Piedmont Park neighborhood in Apopka, Fla., a former agricultural hub now crowded with housing developments. Where one in 10 homes was once a rental, now more than a third are. Caverlyat just moved into the neighborhood. Her home was purchased by an investment group in January and then put on the rental market. (AP Photo/John Raoux) 

In this image from video provided by House Television, House Speaker Paul Ryan gavels the House into session Wednesday night, June 22, 2016, in Washington. Rebellious Democrats staged an extraordinary all-day sit-in on the House floor to demand votes on gun-control bills, shouting down Ryan when he attempted to restore order as their protest stretched into the night. The sit-in was well into its 10th hour, with Democrats camped out on the floor stopping legislative business in the House, when Ryan stepped to the podium to gavel the House into session and hold votes on routine business. Angry Democrats chanted “No bill, no break!” and waved pieces of paper with the names of gun victims, continuing their protest in the well of the House even as the House voted on a previously scheduled and unrelated measure to overturn an Obama veto. (House Television via AP) 

JET Magazine cover of Mary Elizabeth Vroman, October 1955 

Supreme Court justice Sonia Sotomayor at the Smithsonian Museum of American History in Washington, June 1. Sotomayor wrote the dissenting opinion in a Supreme Court decision released Monday that allows evidence seized during illegal traffic stops to be used against citizens if law enforcement discover an outstanding warrant. (AP Photo/Cliff Owen) 

This frame grab provided by Senate Television shows Sen. Chris Murphy, D-Conn. speaking on the floor of the Senate on Capitol Hill in Washington, Wednesday, June 15, 2016, where he launched a filibuster demanding a vote on gun control measures. The move comes three days after people were killed in a mass shooting in Orlando. (Senate Television via AP) 

Normal and sickle shaped red blood cells 

In this June, 27, 2015, file photo, Bree Newsome of Charlotte, N.C., climbs a flagpole to remove the Confederate battle flag at a Confederate monument in front of the Statehouse in Columbia, S.C. After nine black parishioners were slain at a Charleston church, South Carolina did what many thought would never happen: It moved the Confederate flag off Statehouse grounds. But for the most part, Charleston and other areas of the South remain unchanged. (AP Photo/Bruce Smith, File)