What’s a lonely shark to do without her mate? Apparently, make babies on her own. For 4 years, Leonie the zebra shark had been rocking the single life alone in her tank, when she spontaneously birthed three little sharks in early 2016, New Scientist reports. When puzzled researchers tested the babies to find out who the father could be, it turned out there wasn’t one—the DNA was all from mom. One of many surprising details of reproductive diversity, some vertebrates, including sharks, have been found to fertilize their own eggs in the past. But Leonie, who had more than two dozen babies with her mate before leaving him (similar to the baby zebra shark above), has become only the third documented animal to switch from a sexual to an asexual reproducer.
*Correction, 18 January, 4:00 p.m.: An earlier version of this story contained a typo referring to sharks as invertebrates. The article has been corrected.