Xenotransplantation failure dissipated. An American infant girl known as "Baby Fae" with hypoplastic left heart syndrome was the first infant recipient of a xenotransplantation, when she received a baboon heart in 1983. The procedure was performed by Leonard L. Bailey at Loma Linda University Medical Center in Loma Linda, California. Fae died 21 days later due to a humoral-based graft rejection thought to be caused mainly by an ABO blood type mismatch, considered unavoidable due to the rarity of type O baboons. The graft was meant to be temporary, but unfortunately a suitable allograft replacement could not be found in time.
Baboon Guinea baboon is and weighs only , while the largest chacma baboon can be and weigh . Five species of "Papio" are commonly recognized, although there is some disagreement about whether they are really full species or subspecies. They are "P. ursinus" (chacma baboon, found in southern Africa), "P. papio" (western, red, or Guinea baboon, found in the far western Africa), "P. hamadryas" (hamadryas baboon, found in the Horn of Africa and southwestern Arabia), "P. anubis" (olive baboon, found in the north-central African savanna) and "P. cynocephalus" (yellow baboon, found in south-central and eastern Africa). Many authors distinguish "P. hamadryas"