Najin (R) and Fatu, the only two remaining female northern white rhino, graze in her paddock on March 20, 2018 at the ol-Pejeta conservancy in Nanyuki, north of capital Nairobi. Sudan, the last male northern white rhino, has died in Kenya at the age of 45, after becoming a symbol of efforts to save his subspecies from extinction, a fate that only science can now prevent. / AFP PHOTO / TONY KARUMBA (Photo credit should read TONY KARUMBA/AFP via Getty Images)