Spittle bubbles produced from a liquid by Spittle bugs who then hide in it for protection from predators. The spittle also insulates the bugs from temperature extremes plus ensures these insects an adequate supply of moisture so they don't dry out and die. The spittle bubbles are produced when the bug moves its body up and down in a billow like motion causing its body to secrete a goo and air out of its anus. It then uses its hind legs to manipulate the bubble around its body, thus creating its home and protection.