Some lizards have a visible third eye known as a parietal eye, which is an opalescent gray spot on the top of their heads. The eye is sensitive to changes in light & dark but cannot form images. – WTF Fun Facts
Source: http://www.anapsid.org/parietal.html
A mantis shrimp can swing its claw so fast that it boils the water around it and creates a flash of light. – WTF Fun Facts
Goldfish will lose their color and turn white if they are kept in the dark and not exposed to any sunlight. – WTF Fun Facts
Source: https://pethelpful.com/fish-aquariums/Why-do-goldfish-change-color
You weight more when the lights are on – WTF fun fact
