Living snakes area unit found on each landform except land, and on most slighter land lots — exemptions embody some huge islands, like eire and New Sjaelland, and adequately of petite islands of the Atlantic and central Pacific.[1] in addition, ocean snakes area unit common throughout the Indian and Pacific Loads. quite twenty relations area unit presently known, comprising regarding five hundred genera and concerning three,400 species.[2][3] they vary in size from the little, ten cm-long thread snake to the python of up to eight.7 meters (29 ft) long.[4][5] The fossil species Titanoboa cerrejonensis was fifteen meters (49 ft) long. Snakes area unit thought to possess grown from either digging or aquatic lizards throughout the mid-Cretaceous amount, and also the earliest familiar fossils date to around 112 Ma past. the variety of current snakes appeared throughout the Paleocene time amount (c sixty six to fifty six Ma ago). The oldest preserved imageries of snakes are often found within the Brooklyn Papyrus.
Most species area unit atoxic and people that have spleen use it primarily to kill and calm prey instead of for self-protection. Some possess venom potent enough to cause painful hurt or death to human being. anoxic snakes either swig prey alive or kill by compression
