By far, the biggest on the list
Parthenogenesis has been known to occur in several species of shark, including blacktip, zebra, carpet, white-spotted bamboo, bonehead, and even some kinds of hammerhead sharks. The phenomenon has primarily been observed in captivity when females have been isolated from males. Under these circumstances, some females have the ability to switch from sexual reproduction to parthenogenesis. While this is likely an evolutionary trait that allows a species to survive when mates are scarce, some researchers worry it could lead to a lack of genetic diversity and endanger long-term shark survival in the wild.
While many older studies suggest that the offspring of this phenomenon is less equipped for survival, there are examples of fully capable offspring from self-fertilization. However, there is not sufficient evidence on whether parthenogenesis occurs similarly in nature, as all observations of this process has occurred while the shark was in captivity.