Imagine a perfectly preserved, albeit flattened, animal imprint etched into the sidewalk – a bizarre monument to a creature's unfortunate demise. That's exactly what captivated Chicago and the internet: the infamous "rat hole." But hold on, what if everything we thought we knew about this urban legend was wrong? Researchers are now saying it wasn't a rat at all, but more likely a squirrel!
The story began when a comedian's social media post of the imprint, affectionately dubbed "Splatatouille" by the public, went viral in early 2024. Located on West Roscoe Street, the imprint quickly became a local landmark, drawing curious onlookers and sparking countless memes. Sadly, the original "Splatatouille" was removed later that year when the city replaced damaged sections of the pavement.
The central mystery surrounding the imprint was, of course, the creature's identity. Was it truly a rat, as many initially assumed, meeting its end in fresh concrete? Or was there another explanation?
Dr. Michael Granatosky, lead author of a new study from The University of Tennessee, Knoxville, argues for the latter. "I think it’s an eastern grey squirrel. I think that is what the evidence most supports," he states. His team's findings, published in the journal Biology Letters, present a compelling case for the squirrel theory.
Granatosky and his colleagues meticulously analyzed a list of 37 mammal species known to inhabit Chicago. They systematically eliminated candidates based on rarity or anatomical inconsistencies with the imprint. This left them with eight potential culprits, including the brown rat, eastern grey squirrel, eastern chipmunk, and muskrat.
Since the original imprint was no longer available, the researchers relied on publicly available photographs. Using these images, they measured key anatomical features, such as head width. They then compared these measurements to those taken from preserved museum specimens of each candidate species.
While none of the specimens perfectly matched the imprint (and let's be honest, expecting a perfect match after years of weathering is a tall order!), the eastern grey squirrel, fox squirrel, and muskrat showed the closest resemblance. But here's where it gets controversial... The researchers argue that the eastern grey squirrel is the most likely candidate due to its prevalence in Chicago compared to the fox squirrel and muskrat.
"We therefore propose that the specimen be rechristened the ‘windy city sidewalk squirrel’ – a name more fitting of its likely origins and more aligned with the evidence at hand," the team wrote, injecting a bit of humor into their scientific conclusion.
Granatosky further explains that the spreading of the unset concrete could account for the imprint's slightly larger size compared to a typical squirrel. The team also points out that the concrete was likely wet during the day, coinciding with peak squirrel activity. And this is the part most people miss... The presence of nearby trees, combined with the apparent impact angle, suggests the animal may have fallen from a significant height.
Now, some of you might be thinking: what about the tail? The imprint showed no sign of a bushy tail, a signature feature of squirrels. The researchers address this concern, explaining that fine details like hairs are best preserved in fine silt, not coarse concrete.
But here's a thought: could the lack of a tail impression also suggest a juvenile squirrel? Or perhaps the tail was positioned in such a way that it didn't leave a clear mark? This is where the interpretation gets tricky, and it highlights the challenges inherent in studying trace fossils.
Granatosky emphasizes that while the study's subject matter might seem frivolous, it underscores the power of scientific inquiry to address diverse questions. More importantly, it reveals the inherent difficulties in interpreting traces left behind by organisms – a fundamental aspect of paleontology.
"When we step in mud, or concrete in this case, things spread out, things move, there are many different layers within the track, and so it’s a hard science," he explains. The process of fossilization and trace preservation is complex, influenced by numerous factors that can alter the original form.
So, what do you think? Are you convinced that "Splatatouille" was actually a squirrel? Or do you still believe a rat is the more likely culprit? Could there be other factors at play that the researchers haven't considered? Share your thoughts and theories in the comments below! Let's continue the debate and see if we can collectively unravel the mystery of the Windy City's sidewalk imprint.
