Of all the types of cartilaginous fish, this is the only one that exhibits melanism. el biodiversity center on Lady Elliot Island was observed a particular specimen of a rare species of melanic manta ray
Lady Elliot Island, at the southern end of the Great Barrier Reef, is a great center of biodiversity. Its clear waters are home to a multitude of different species of flora and fauna, as well as some very unique manta rays. These are the melaniche, which show a particularly dark color, practically black. The latest sighting was made by marine biologist Jacinta Shackleton, and it is quite a rare and beautiful event. According to Asia Haines of the Manta Project, about 80 of the 1,400 specimens identified on Lady Elliot Island are melanics, or 7.5% of the local population. Worldwide, the picture is even more impressive, because of all the hundreds of species of cartilaginous fish in the ocean, manta rays are the only ones to exhibit melanism.
The Characteristics of Melanistic Mantas
Melanism is a term used to describe living things whose body tissues are darker due to an excess of melanin, which results in some beautiful black hues in a host of animals, including reptiles, birds, seals and, especially, big cats. At IFLScience, Shackleton said not all melanic animals are black and some can be identified by spots or patterns.
The cause that causes some mantas to be darkly colored is not yet known, but a 2019 study ruled out some hypotheses. Scientists had thought that the variation might depend on this particular species' ability to camouflage itself, but a long-term analysis showed no difference in survival rates between white and black manta rays. One detail that has been noted, however, is that melanism rates differ markedly depending on the locality in which they are found. With 7.5% of the local population of black manta rays, Lady Elliot Island, for example, has far fewer of them than the 40% of manta rays in the Raja Ampat Islands.
On Lady Elliot Island in addition to the black type, there are also other rare species of manta rays, such as the only known pink specimen in the world, called the Inspector Clouseau. The so-called "manta house" is also home to several pale and white specimens, such as the Bull, the oldest recorded manta ray in the world at the venerable age of 40 years. The world of the deep is still full of mysteries between unknown species, adaptation and ability to interact between different specimens. A research of the biology department of Washington University has discovered, for example, that a type of fish, the Mormyridae, would be able to "talk" to each other almost as if they were human beings.
Stefania Bernardini