An Arizona man who calls himself "The Desert Whisperer" came across a sleeping diamondback rattlesnake and decided to start filming.
The rattlesnake can be seen catching some Z's in a shady wooded area. The cameraman zooms in and out as the snake is totally unaware of his presence.
All of a sudden, the snake woke up in a very menacing way, all coiled up and rattling its tail very aggressively. Try watching this video (below) without jumping out of your seat!
Rattlesnakes use their rattle to warn others, according to the YouTube video.
"They may rattle to indicate they are present so they won’t be stepped on, or they may rattle if cornered or harassed to warn that they may be about to strike."
Obviously, it's not a good idea to disturb a sleeping rattlesnake.
Photo: Getty Images