Those tortoises are now between seven and 11 years old. Smith's work focuses on social behavior and endocrinology. She's using behavior observations and hormonal analysis to find answers. That would be a clear head-start. Smith and her Las Vegas colleagues began by pairing up each superjuvie with an opposite sex adult then watching what occurred.
Females signal their willingness to mate by staying still.
Otherwise, they just walk away. They collected blood samples to compare hormone levels of the superjuvies to levels in adults. They also collected and artificially incubated all eggs that were laid to find out whether those eggs were fertile. While Smith has not yet finished analyses of the behavior and hormonal data, all the eggs from 1996 did hatch. Male superjuvies, on the other hand, were able to successfully fertilize their partner's eggs.