Why a moth would seek an animal’s eye
Nectar is rich in sugars, which provide energy, but it can be a poor source of sodium. Animals’ tears contain dissolved salts, including sodium, so a moth that drinks them can obtain a mineral that may be scarce in its usual food. Sodium helps maintain the electrical signals used by nerves and muscles, among other basic functions.
This behavior is called lachryphagy, meaning the feeding on tears. It is one way insects can supplement a diet that does not supply every nutrient in the same proportions.
A tiny feeding tool, used at close range
A moth’s proboscis is a long, flexible mouthpart that works like a straw. The moth can extend it to take up liquid while keeping its body away from the animal’s eye. Because the meal is small and the animal is resting, the moth may be able to feed without provoking an immediate response.
That makes a sleeping mammal an unusual mineral source: not a plant, but a living animal whose tears carry dissolved salts. The scene is a reminder that an insect’s menu can be shaped not just by calories, but by nutrients that ordinary nectar may lack.
