A recent video claimed to depict a bizarre river monster has surfaced along with questions about its authenticity. The video shows a long, snake-like form apparently swimming in glacial river in eastern Iceland.

Could it be Lagarfljótsormurinn, a lake monster of Icelandic legend?

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Some say yes; others aren’t so sure… There are a few things that it pretty much could not be, starting with what it appears to be: a snake. Snakes are exothermic; they can’t regulate their body temperature and must depend on the environment to do so. That’s why snakes in the wild can sometimes be seen basking in the sun early in the morning—they’re trying to warm up. While some species of snakes are aquatic, they typically live in much warmer climes; the last place a snake would want be is an ice-filled stream. Another sign that it’s not a snake or living animal is that the length of it is unnaturally segmented. At one point when the “tail” is moving it creates almost a 90 degree angle, not an organic smooth curve.

Because of the poor quality, shakiness, and brevity of the footage, it’s not even clear that the would-be monster is actually moving. It seems to be heading upstream, but that could just be an illusion created by the water moving past it. It could be making progress toward the shore—or its head might be simply sitting there, more or less stationary in the water while the “body” contorts with the current. To really know, we’d need to see more than a short clip; if it’s still in the same spot after a minute or two, then it’s not making forward progress and therefore not a living creature.

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There’s something else very suspicious about this video: It seems to have been shot by two different people with two cameras—or at least from two different angles.

It begins with a wide shot, and then cuts to a closer-up one, but the closer-up one seems to be much lower and head-on, instead of from above and to the right. The final video intercuts the two different clips, raising the question of why. If there are two different, genuine videos of the “animal,” why not just show both of them in their entirety, instead of editing and manipulating the footage?

The other possibility is that the cameraman got a long shot, then moved down to the bank to get a closer image from a lower angle, closer up. But if it really was an animal moving at the speed it seems to, it’s likely that it would have been gone—or come ashore—by that time.

The most likely explanation is that the video is a hoax—either the photographer (or his or her friends) were manipulating an object to make it look like it was swimming, or they happened to notice a natural, inanimate object in the water (such as a fishing net or piece of cloth) and decided to videotape and present it as a mystery.

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If the video is fake, it’s only one of many recent hoaxes. Just this past week another video—coincidentally also from a river in a cold climate, this one in Siberia—made the news as an alleged woolly mammoth. Both videos seem about equally plausible.

Photo credit: YouTube