The RSPCA based in Horsham, England, said it commissioned the study after several high-profile cases of elephant mistreatment, including one in which electric prods were being used to train elephants at a British zoo. The authors births and deaths from a studbook of elephants at collected data on European zoos to assess life expectancy and infant mortality. Studbooks catalogue the family history E of animals in captivity, especally to help prevent inbreeding. The studbook 40 years of births spans and deaths for African savanna elephants (Loxodonta Africon) and nearly 100 years for Aslan elephants Elephas Maximus) in European zoos. An estimated 500 elephants, 48% of the world's zoo elephant population, are now in zoos across Europe, from Belfast to Paris. Sty-nine elephants live in UK zoos. The researchers also reviewed more than 100 elephant studies published since 1960, as well as 500 studies on stress biology and the welfare of other captive animals