In the World of Shark Research, a Big Retraction

As far as retractions go, it's an unusual one: A group of scientists have yanked their May 2022 paper claiming a goblin shark had been sighted for the first time in the Mediterranean as well as their defense, published March 13, 2023, of their study. The March 20 move came amid criticisms that the specimen that was discovered wasn't a genuine shark but rather a toy. Their record, published in Mediterranean Marine Science, was based solely on "citizen science": a photo of the creature taken on the shores of Greece’s Anafi Island in 2020. The image didn't contain anything that would establish a sense of scale, and the shark wasn't collected but was instead left to the sea. The standout twists and turns:

• Why the find would have mattered. It would have just added to a very limited number of sightings of the mysterious creature, which lives at depths of up to 4,300 feet and has an unknown lifespan. The Daily Beast reports fewer than 50 goblin sharks have been documented.
• Why the find would have mattered II. It wouldn't have just been a first for the region, but a first with potential implications, per Gizmodo: "If the 2022 record were genuine, it would represent an important range extension that could dictate future research funding or even marine conservation spending."
• But it didn't look so genuine. At least to critics, who flagged certain purported anomalies, like four gill slits when there should be five, a protruded jaw, and unnatural stiffness—and found a toy shark that looked a lot like it. It was also small: The researchers described it as a maximum of 80 cm in length initially, and more like 20 cm in their rebuttal; LiveScience reports the smallest goblin shark ever documented measured 107 cm.
• The study authors' rebuttal. They suggested its small size may have been because it was an embryo.
• The study authors' continued defense. Despite the retraction, co-author Frithjof Kuepper had this to say to the Daily Beast: "Even though we have every reason to assume that the finding was authentic (several Mediterranean shark experts and [two] anonymous peer reviewers accepted and supported publication of this paper!), other colleagues caused a completely unethical controversy." Kuepper said the retraction occurred "to avoid further damage."
• About that peer review. LiveScience notes the peer review process isn't without its critics, and it flags one big issue: Experts aren't paid to review studies, which increases the likelihood reviewers could end up giving studies a quick scan rather than take a deep dive into the results.
• Parting advice from Gizmodo: "If you think you’ve found a dead one, maybe give it a good squeeze—just to be sure."

(More strange stuff stories.)