Identifying whether bite marks are from rats or squirrels is challenging due to their similar dental structures, which consist of ever-growing teeth and a diastema. According to research published in the journal Animals, both rodents can create similar damage on various surfaces, leading to potential misidentification. Studies in the Journal of Experimental Biology indicate that while rats adapt their chewing from incisors to molars, squirrels rely more on incisors, resulting in different bite angles and depths. Additionally, the material of the surface affected by the bite can significantly alter the appearance of the marks. For instance, a bite mark on plastic will differ from one on wood, complicating visual assessments. A study in the Journal of Forensic Sciences highlighted that brown rats prefer softer bones, while gray squirrels target harder ones, suggesting that feeding behavior also influences damage. A notable case in 2025, the “Chicago Rat Hole,” was misidentified as a rat hole but was later determined to be made by a squirrel through detailed analysis. This underscores the importance of careful measurement over assumptions when assessing rodent activity.