Mysterious Orange Shark With Piercing White Eyes Stuns Scientists Off Costa Rica’s Shores
A Nurse Shark With Overlapping Pigmentation Conditions Astonishes Researchers
According to research from the Federal University of Rio Grande, the orange appearance is believed to have been caused by a condition known as xanthism, or xanthochroism, which creates excessive yellow or golden colors in an animal’s skin due to a lack of red pigmentation.
Curiously, the shark also showed signs of albinism, including a pair of all-white eyes. Both of these conditions — the orange skin and white eyes — are antithetical to nurse sharks’ natural camouflage.
Tortuguero National Park/FacebookA fisherman named Juan Pablo caught the shark last year on a fishing trip.
Typically, these sharks have brown skin and dark eyes that allow them to naturally blend into the seabed, making them less vulnerable to predators. Nurse sharks are also benthic predators, meaning they spend a majority of their time on the seafloor around reefs and rocky ledges stalking prey. In theory, bright orange skin would make it more difficult to hunt and to hide.
Researchers, however, suggested this may not be the case.
The discovery also raises questions about the nature of the condition. While xanthism is known to have a genetic basis, the study authors pointed out that other factors such as “inbreeding, environmental stress, elevated temperatures, and hormonal imbalances may also influence pigmentation.”
Xanthism itself is considered rare in the animal kingdom, only observed in a few other fish species. Among freshwater species like guppies, cichlids, and goldfish, it is sometimes seen to create vibrant yellow variations. Birds like parrots and canaries, meanwhile, have also displayed golden plumage linked to xanthism. For it to occur alongside albinism, however, is almost entirely unheard of.
Post Comment