Why would a bird with a blue hat be so thirsty? It's not the hat, it's SCIENCE!
When the bird is manufactured, most of the air is removed from the inside. The gas that remains is largely the vapor from the red liquid, which vaporizes very easily. When the fuzzy coating on the bird's head is wet, water evaporates and cools the vapor inside the bird's head. This condenses the vapor back to red liquid and reduces the pressure in the bird's head. When the fuzzy coating on the bird's head is wet, water evaporates and cools the vapor inside the bird's head. This condenses the vapor back to liquid and reduces the pressure in the bird's head. The bird's head keeps moving.
Since the pressure of the vapor in the bird's body is now higher than the pressure in its head, liquid is forced from the bottom up the tube toward the head. As the liquid moves up the tube, the center of gravity of the bird is raised, and the bird begins to tip around its fulcrum. When the bird finally dips into the water, a clear passage is opened between the head and the body, allowing the pressures to equalize and the liquid to fall back down to the body. The bird returns to the upright position and the whole process repeats.
Each time the bird's beak dips into the water, the fuzzy material absorbs a little water to replace any that has evaporated. This prevents the bird's head from drying out. The bird will continue its cycle until the head dries out, and evaporation can no longer cool it.
In summary, here are the basic steps of the cycle.
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