Scuba divers in Indonesia were thrilled to see a school of giant manta rays drifting casually past them. But even more amazing was the fact that one of them was entirely black, except for a few white spots on its underbelly. These mantas typically have white underbellies and white markings on their backs. Referred to as melanism, it is highly unusual in marine species. In terrestrial animals, it is much more common. AN example is black panthers, which are actually jaguars with a colour differentiation. Although this phenomenon has been occurring more frequently in recent years, it is specific to manta rays. No other shark or ray species exhibits this melanism. Scientists are fascinated with this development. Recent studies have revealed that there is a significant population of black mantas in Raja Ampat, Indonesia as well as Ecuador. The confusing part for researchers is that these two populations have shown up despite the great geographical distance between the two regions. This has produced more questions than answers. Scientists have explored whether this colouration affects survival rates. There has been no evidence to suggest that predators are more or less likely to target black mantas. Understanding melaism among manta rays will help scientists understand the migration and breeding habits of mantas as they explore the possibility that this trait has been spread because different manta ray populations are connected. As we learn more about animals and about the world around us, we also learn how much we don't yet know.