Another now extinct species the zoo held was a number of thylacines, or "Tasmanian tigers". The research enhanced hopes of eventually restoring the population of thylacines. He was assisted by two thylacines named Benjamin and Natasha. Thylacines only once bred successfully in captivity, in Melbourne Zoo in 1899. Like with thylacines, it is very likely that they possessed long cartilaginous elements instead. Phylogenetic analysis shows that thylacines are a clade which does not include the dasyurids.