Rattlesnake is a kind of tube tooth poisonous snake of Agkistrodon halys family of Reptilia. The snake venom is blood circulating poison. It is yellowish green, with diamond black brown spots on its back. When the horny ring at the end of its tail swings, it can make a loud sound for a long time, so that the enemy dare not approach or be scared away.

At the tip of the rattlesnake's tail, there is a horny chain ring, which surrounds a cavity, and the horny membrane separates the cavity into two annular vacuoles, like two air oscillators. When the rattlesnake wags its tail constantly, an air flow is formed in the bubble, which oscillates back and forth in and out, and the bubble makes a sound.

Source: @babsie_tatts