Thankfully, they're not killer Sharktopuses (sharktopi?). However, the Australian black-tip shark has been found to be mating with their global counterpart, the common black-tip.
This is the first time it has been observed in nature. It is significant because the Australian black-tip is smaller and can only survive in tropical climates. Scientists are calling this "evolution in action" becuase the hybrids can survive in more climates.
They still don't know if the hybrid breed has the upper hand in the evolutionary chain. If they do, then they expect the Australian black-tip to slowly disappear over time.