A quirky hole in a Chicago sidewalk became famous for its resemblance to a rat. People flocked to it, leaving coins and gifts. But a recent study reveals that this “Chicago Rat Hole” was likely made by a squirrel.
Researchers analyzed the hole and compared it to local rodent data. They published their findings in the journal Biology Letters. Their investigation suggested that the dent came from an eastern grey squirrel or a fox squirrel, not a rat.
Michael Granatosky, the study’s lead author from the University of Tennessee, Knoxville, shared that people initially assumed the hole was made by a rat. “Just assuming isn’t the best approach in science,” he noted.
The hole had actually been around for years before it went viral. Winslow Dumaine, a Chicago-based artist, posted about it on social media, turning the hole into a local tourist spot in early 2024. In his post, Dumaine even called for a “pilgrimage” to see the hole.
Dumaine said, “Squirrels are a lot more TV-ready than rats.” He believed the “rat” label fueled its popularity.
While some social media users questioned the hole’s appearance, researchers found it odd for a rat to make such an impression without leaving footprints nearby. This led them to delve deeper into the mystery. Using the citizen science app iNaturalist, they examined local animal data, which hinted at a four-legged creature with distinctive features.
Although city officials removed the hole in April 2024 to ease crowd disturbances, the researchers had plenty of photos for analysis. They measured the hole against specimens at the American Museum of Natural History and determined a 98.7% chance it belonged to a squirrel.
Given this revelation, the researchers proposed renaming the hole to “Windy City Sidewalk Squirrel” to reflect its true origins.
This fun twist on science serves as a reminder: the scientific method can be accessible to everyone. Edwin Dickinson, a senior author and archaeologist at the University of Calgary, emphasized the joy of discovery. He hopes that more people will engage with science, finding excitement in even the simplest observations.
So, the next time you see a curious formation in the concrete, take a moment to ponder its origins—science can be as entertaining as it is enlightening!
