When a creature appears and refuses to sit in any of the tidy drawers designed for it, biology is filled with a subtle kind of embarrassment. That’s what’s happening right now, and it’s happening in the shadowy crevices of the Japan, Ryukyu, and Izu-Ogasawara trenches at a depth that most people will never see in their lifetimes—roughly 9,137 meters below the Pacific’s surface.
The discovery was made during a 2022 expedition sponsored by Caladan Oceanic and Inkfish and headed by the Tokyo University of Marine Science and Technology and the University of Western Australia’s Minderoo Deep-Sea Research Centre. On board the DSSV Pressure Drop for two months. Trawls should be replaced with submersibles. Baited and dropped into the black, free-fall landers waited patiently for whatever happened to pass by. 108 different organism groups were recorded by the team. It would have been a successful trip just for that. However, hidden within the video was something else: a slow-moving animal that no one on the boat recognized and no one has been able to identify since.
It was once filmed. Then they filmed it again, almost as if to make sure it wasn’t a dream. The two encounters took place close to the same crushing depth. Carefully choosing their words, the researchers described it as “the most enigmatic encounter” of the expedition. It’s clear from reading between the lines that they were shaken. Words like “baffling” are rarely used by marine biologists unless they truly mean it.
The fact that this isn’t an isolated incident is what makes it strange. A different team in Copenhagen has been grappling with a tiny mushroom-shaped creature that was removed from the ocean in 1986 and wasn’t thoroughly studied until decades later. It is only a few millimeters across and is a flattened disc with a stalk and a mouth. The samples were left in alcohol for years, which may seem like a good way to preserve them, but keep in mind that alcohol destroys DNA. Thus, the most potent tool available to modern biology—the one that would typically resolve the dispute in an afternoon—is no longer available.
According to Jorgen Olesen of the University of Copenhagen, there have likely been four instances of this type of incident in the past 100 years. Four. For a planet this size, that is an incredibly small number. He won’t elaborate, but he believes the creature belongs in the animal kingdom, most likely close to the jellyfish family. His candor is welcome. He will claim that it is incompatible with the bilateria, a vast group of animals that includes humans and have a front and a back, a left and a right. There is a top and a bottom to this object. That’s all.
Reading the papers gives me the impression that these organisms could be echoes. The Ediacaran period, which occurred between 635 and 540 million years ago, is so poorly understood that its fossils continue to cause controversy at conferences. The specimens from Copenhagen bear an unsettling resemblance to these creatures. The consequences are subtly huge if even a distant relative of that fauna is still floating around down there. It would imply that whole branches of life have been lurking in plain sight, just out of the trawl net’s reach.
It’s difficult to ignore the researchers’ own tone. Olesen described his team’s published paper, almost sheepishly, as a “cry for help.” They are requesting that museums, academic institutions, private collections, and anybody else look through old jars to see if a sample that has been forgotten can still be preserved sufficiently for DNA analysis. For science, which typically favors confidence, that is an odd stance. Here, the lack of confidence is deliberate.
Watching this unfold, you get the sense that the ocean has been keeping a kind of joke at our expense. The resolution of our mapping of Mars is higher than that of the abyssal plains. We send rovers to other planets while something quietly glides past a camera in our own backyard and we can’t even tell it what it is.
Perhaps that’s the true lesson. There are still empty branches on the tree of life. All we need to do is be looking in the correct place and be prepared to acknowledge our ignorance.
