A dolphin with unusual, hook-shaped “thumbs” on its flippers has been discovered in the Gulf of Corinth.
According to livescience, researchers from the Pelagos Cetacean Research Institute found the dolphin during boat surveys off the coast of Greece this summer. Despite its unique flippers, the dolphin kept up with its group and engaged in typical dolphin activities like swimming and playing.
This is the first time such flipper features have been observed in 30 years of studying dolphins in the open sea and along the Greek coasts.
The Gulf of Corinth, located between the Greek mainland and the Peloponnese peninsula, is home to a diverse community of dolphins. The unusual dolphin is a striped dolphin, and there are approximately 1,300 of them in the Gulf of Corinth, separated from the rest of the Mediterranean population.
The strange flipper does not seem to be a sign of illness but may be a result of rare and irregular genes caused by continuous interbreeding in the isolated population.
“Normally, dolphins develop their fingers within the flipper and no cells between the fingers die off,” Lisa Noelle Cooper, an associate professor of mammalian anatomy and neurobiology at the Northeast Ohio Medical University, said.
However, the photographed dolphin seems to be missing some fingers and the accompanying tissue.
“I’ve never seen a flipper of a cetacean that had this shape,” Cooper told Live Science in an email. “Given that the defect is in both the left and right flippers, it is probably the result of an altered genetic program that sculpts the flipper during development as a calf.”