"Much like a chicken, they will lay eggs if the conditions are good, whether they are fertile or infertile," Dudgeon told The Guardian Australia.
Despite the lack of male sharks, six of Leonie's 47 eggs had live embryos inside. However, by the third month of incubation, all six had died.
Again, both sharks laid eggs last year. Four of them hatched – three from Leonie's clutch and one from Lolly's.
It's incredibly rare for females of a species to switch from sexual to asexual reproduction. There are only two other documented cases, according to The Guardian. An eagle ray who was separated from her partner for a year managed to reproduce and a boa constrictor asexually reproduced, although she was caged with a male boa constrictor, according to the newspaper.
It's not clear what caused Leonie to switch from sexual to asexual reproduction.
"What we want to know now is, could this occur in the wild and, if so, how often does it?" Dudgeon said. "This has big implications for conservation and shows us how flexible the shark's reproductive system really is."
However, she warned The Guardian, the switch is unlikely to herald a turning point for the endangered species. She described the case to the newspaper as similar to "a severe case of inbreeding."
Scientists will watch Leonie's offspring to determine whether they can reproduce despite their odd beginnings.
"You lose genetic diversity with generations of asexual reproduction, so we'll be seeing if these offspring can mate sexually themselves," Dudgeon said.