The photo is authentic and it depicts a whale's front fin bones that resemble human hand bones.
The creature visible in the image is a sperm whale, not a gray whale.
For several years an image allegedly depicting a "front fin bones of a Grey whale" circulated on social media platforms such as Reddit, 9GAG, Facebook, and X, formerly known as Twitter, reaching (at least) hundreds of thousand of views.
? Whales have arm, wrist & finger bones in their front fins. This is the front fin bones of a Grey whale.
byu/Browndog888 inNatureIsFuckingLit
The copied-and-pasted description of the viral image read "Whales have arm, wrist & finger bones in their front fins. This is the front fin bones of a Grey whale."
We tracked down the source of the image. TinEye and Google reverse-image search results indicated that the image has been shared online at least since 2017. When we investigated further, we found out that the photo was authentic and it dated back to February 15, 2017. The image was shared on various Chinese-language news websites and in numerous social media posts.
Bone of whale's fin, spine section & teeth. Good proof that humans evolve from marine lives https://t.co/eQwqFioBL6 pic.twitter.com/5HoI2ISNd9
— China Xinhua News (@XHNews) February 15, 2017
Xinhua News Agency, an official state news agency of the People's Republic of China, and China Central Television (CCTV) were among the first to share the picture of this seemingly unlikely discovery. "Bone of whale's fin, spine section & teeth. Good proof that humans evolve from marine lives," the X caption of Xinhua News Agency's post read. However, the in-question photo did not show the fin of a gray whale, but rather that of a sperm whale. The CCTV post with the image in question read:
Two sperm whales became stranded near the Yangkou Port in Rudong County, East China's Jiangsu Province on Feb. 14, 2016, and they were later made into specimens in Shanghai and Dalian. Now, one specimen has returned to the port for exhibition.
A 2018 research paper with the title "The myodural bridges' existence in the sperm whale" referenced the 2016 incident, as the whale was shared by Chinese authorities for the purpose of scientific research:
A 15.1-meter long sperm whale was acquired opportunistically examined in this study from stranding with the permission of Chinese Authorities for Animal Protection. It died naturally in the beache of Nantong (Jiangsu province, China). The cadaver was permitted for scientific research under the approval of the Ethics Committee of Dalian Medical University.
Some social media users were surprised that whales' bones had a so humanlike appearance. American Museum of Natural History explained that "the sperm whale's flippers, or pectoral fins, help the animal maneuver through water."
(American Museum of Natural History)
Moreover, the museum underscored that the sperm whale's bone structure is similar to human bones:
They also share bone structure with the human arm and hand. In fact, the bones of cetacean flippers are the same kinds of bones as in the human arm, with an upper arm bone, two forearm bones, and hand, wrist, and finger bones. In whales, fingers are elongated and may have additional bones. The joint between upper arm and forearm is immobile, creating an effective paddle.
Whales Online, a magazine published by the Group for Research and Education on Marine Mammals (GREMM), published an article referring to the whales' front limbs (emphasis ours):
The front limbs of whales' land-roaming ancestors grew much shorter and transformed into pectoral fins. The bones are no longer articulated and do not allow for any movement. The only point of articulation is the shoulder. These fins serve both as a stabilizer and a rudder. Five digits for toothed whales and right whales, four for rorquals: some are very long, with many more phalanges than in land mammals. The bones of the hand are embedded in a fibrous, rigid and resistant tissue and do not appear at the surface of the skin.
And here's what the whale's full skeleton looks like:
(baleinesendirect.org screenshot)