Behold our new cetacean overlord: a dolphin has been spotted with thumb-like appendages on its flippers, because the world apparently wasn't weird enough yet.

As Live Science reports, scientists at Greece's Pelagos Cetacean Research Institute have twice seen the morphed marine mammal when doing boat surveys in the country's semi-enclosed Gulf of Corinth — and they're just as intrigued as we are.

"It was the very first time we saw this surprising flipper morphology in 30 years of surveys in the open sea," Pelagos' scientific coordinator Alexandros Frantzis told Live Science, "and also in studies while monitoring all the stranded dolphins along the coasts of Greece for 30 years."

Also known as the Corinthian Gulf — yes, as in that one book in the Bible — the region where the bethumbèd creature was found is home to different types of dolphin, including the common dolphin, Risso's dolphins, and the striped dolphins. The rare specimen Frantzis and his team witnessed was a striped dolphin, Frantzis told the website.

With some 1,300 striped dolphins cruising the waters of the Gulf of Corinth, the animals are cut off from the rest of their kind in the Mediterranean Sea — an isolation that may explain how this seemingly genetic abnormality came about. According to Frantzis, the thumb on the striped dolphin he saw and eventually photographed "does not look like illness at all," and could instead be "the expression of some rare and 'irregular' genes" that stemmed from the isolated species' interbreeding.

All said, this thumby boy (or girl — the scientists didn't specify a sex) had no trouble keeping pace with its pod, and was seen "swimming, leaping, bow-riding, playing" along with the others, the Pelagos researcher described.

As surprising as this thumbed Corinthian creature is, experts who spoke to Live Science said that dolphins technically do have fingers — and this one seems to be missing some, rather than having extras.

Scientists have long known that cetaceans, or the group of marine mammals that includes dolphins, whales and porpoises, evolved to have forelimbs replete with extender phalanges or finger bones. According to Swiss doctoral student Bruna Farina, those bones are arranged into human-like "hands" that include thumbs, but normally those digits are concealed by the animals' flippers.

As mammalian anatomy expert Lisa Noelle Cooper told the website, the cell expression in dolphins leads those bones to form into flippers rather than humans' paddle-like hands. But with the dolphin found by Frantzis and his team, it seems the animal in question is missing fingers and the encasing flipper tissues that hide them.

"It looks to me," Cooper continued, "like the cells that normally would have formed the equivalent of our index and middle fingers died off in a strange event when the flipper was forming while the calf was still in the womb."

While the dolphin's quote-unquote "thumbs" may look similar to the digits we sport on our hands, it doesn't appear to be opposable, which sets humans and our primate ancestors apart from other animals.

"The hook-shaped 'thumb' may have some bone inside of it," Cooper said, "but it certainly isn't mobile."

More on weird animals: Scientists Unearth Skull of Terrifying Sea Monster

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