species never to have been domesticated, was recovered from the brink of extinction by a captive breeding program, and successfully reintroduced in the 1990s to the Mongolia, with more than 750 wild roaming Przewalski’s horses today. The Galápagos tortoise population, once reaching as low in population as 12 remaining individuals, was recovered to more than 2000 today by a captive breeding program. A further 8 tortoise species were supported by captive breeding programs in the island chain. Wild Tasmanian devils have declined by 90% due to a transmissible cancer called Devil Facial Tumor Disease. A captive insurance population program was started, but the captive breeding rates as of 2012 were lower than they needed to be. Keeley, Fanson, Masters, and McGreevy (2012) sought to "increase our understanding of the estrous cycle of the devil and elucidate potential causes of failed male-female pairings" by examining temporal patterns of fecal progestogen and corticosterone metabolite concentrations. They found that the majority of unsuccessful females were captive-born, suggesting that if the species' survival depended solely on captive breeding, the population would probably disappear. In 2010, the Oregon Zoo found that Columbia Basin pygmy rabbit pairings based on familiarity and preferences resulted in a significant increase in breeding success. In 2019, researchers trying to breed captive American paddlefish and Russian sturgeon separately inadvertently bred sturddlefish - a hybrid fish between the two fish. Methods used To found a captive breeding population with adequate genetic diversity, breeders usually select individuals from different source populations—ideally, at least 20-30 individuals. Founding populations for captive breeding programs have often had fewer individuals than ideal because of their threatened state, leaving them more susceptible to challenges such as inbreeding depression. To overcome challenges of captive breeding such as adaptive differences, loss of genetic diversity, inbreeding depression, and outbreeding depression and get desired results, captive breeding programs use many monitoring methods. Artificial insemination is used to produce the desired offspring from individuals who don't mate naturally to reduce effects of mating closely related individuals such as inbreeding. Methods as seen in panda pornography allow programs to mate chosen individuals by encouraging mating behavior. As a concern in captive breeding is to minimize the effects of breeding closely related individuals, microsatellite regions from an organisms genome can be used to determine amounts of relationship among founders to minimize relatedness and pick the most distant individuals to breed. This method has successfully been