Pigs are seen in temporary cages as they wait for embryo implementation from genetically altered pigs, at Revivicor Research farm in Blacksburg, Virginia, on November 20, 2024. On a farm in the southern US state of Virginia, David Ayares and his research teams are breeding genetically modified pigs to transplant their organs into human patients. Revivicor, the biotech company Ayares leads, is at the forefront of xenotransplantation research -- the implantation of animal organs into humans -- which aims to solve a chronic organ shortage that has thousands of Americans dying each year. It was on this farm that Revivicor bred a pig whose kidney was recently transplanted into patient Towana Looney, according to an announcement made December 17, 2024 by a New York hospital. (Photo by Andrew Caballero-Reynolds / AFP) (Photo by ANDREW CABALLERO-REYNOLDS/AFP via Getty Images)