Why do rats bite eyelashes? - briefly
Rats gnaw at eyelashes because they explore objects with their teeth and may mistake the hairs for parasites or food, especially when stressed or experiencing dental discomfort. This behavior reflects their innate chewing instinct and curiosity.
Why do rats bite eyelashes? - in detail
Rats often gnaw at human eyelashes because the hair provides a soft, movable target that satisfies their natural chewing instinct. Their incisors grow continuously, requiring constant abrasion; loose lashes offer an easy material to wear down teeth without damaging harder surfaces.
The behavior also stems from exploratory feeding. Rats are omnivorous and opportunistic; when they encounter unfamiliar objects, they investigate by biting. Eyelash fibers contain keratin, a protein that some rodents can digest in small amounts, supplying a marginal nutritional benefit.
Stress and confinement increase oral activity. In laboratory or densely populated environments, rats may redirect excess energy toward novel stimuli, and human facial hair becomes an accessible outlet. The tactile feedback from the fine hairs stimulates the rats’ whisker receptors, reinforcing the action.
Social grooming can trigger the response as well. Rats engage in mutual cleaning, and when they are handled, they may attempt to groom the caretaker’s face, mistaking lashes for fur. This mimics natural group grooming among conspecifics.
Finally, sensory curiosity plays a role. The movement of eyelashes during blinking presents a dynamic object that attracts the rats’ attention. Their acute sense of touch and vibration detection makes the subtle flutter an enticing target for investigation.
Overall, the combination of dental maintenance, opportunistic feeding, environmental stress, grooming instincts, and sensory attraction explains the propensity of rats to nip at human eyelashes.