However even 18 hours is not considered abnormal for a Chihuahua. This includes naps.There are 2 types of sleeping. One is a lighter sleep (called slow wave) and the other is the deeper sleep (known as REM-Rapid Eye Movement). Dogs, just like humans do have these 2 different types of sleep.
Probably the best known snake in the world, the Rattlesnake is a pit viper found almost everywhere in the United States, and is capable of a deadly bite. Its trademark rattle strikes fear into anyone who hears it.
When most people think of poisonous snakes, the rattlesnake springs to mind pretty quickly. These snakes are found throughout the Americas and are actually a type of viper. Their name comes of course from the rattle which is found at the end of the tail and which creates a distinctive noise.