On 6 January 2024, Chicago comedian Winslow Dumaine photographed the near-perfect impression of what looked like a brown rat on a sidewalk in Roscoe Village, a neighbourhood in the north of the city.
The so-called 'Chicago Rat Hole' – a cartoon-like splat complete with tail and claws – had been known to residents for years, but when Dumaine posted the image on social media, it suddenly shot to fame. People flocked to the area from miles around just to get a glimpse of the mysterious hollow.
But despite the hole's rat-inspired name, some locals questioned the creature responsible for it. Now, according to a new study published in Biology Letters, researchers say the culprit was in fact not a rat, but more "likely a squirrel".
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Using anatomical measurements of the imprint from photographs, the scientists compared the outline of the body, tail and claws with museum specimens of commonly observed animals in the Chicago area, including rats, mice, squirrels, chipmunks and muskrats.
"Our analyses offer little support for the hypothesis that the ‘Chicago Rat Hole’ was made by a brown rat," says the study, which suggests that the impression most closely resembles the eastern grey squirrel, fox squirrel or possibly the muskrat – a stocky, semi-aquatic rodent with webbed feet.
While admitting the light-hearted nature of the study, the researchers also point out the value of social media when it comes to engaging the public with the wild animals that live alongside humans in some of our biggest cities.
Top image: Winslow Dumaine, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons
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