"Science on the Web 69" from HowItWorks - "Creepy Cat Eye Glow"

https://youtu.be/HaOIM2sF4v4?is=1Fpu627gbc8WQpvs

Cats eyes "power-up" because of the **tapetum lucidum** - an iridescent, mirror-like, layer behind their retinas. In darkness, their pupils dilate to expose more of the tapetum lucidum, reflecting light back through their eyes in order to improve their night vision - and to give them supurrnatural powers.

Many other animals also have tapetum lucidum - but humans do not.