One might think having no limbs would put a damper on the love life, but not for snakes. When a female snake is ready to mate, she begins to release a special scent (pheromones) from skin glands on her back. As she goes about her daily routine, she leaves an odor trail as she pushes off resistance points on the ground (See Getting Around). If a sexually mature male catches her scent, he will follow her trail until he finds her. The male snake begins to court the female by bumping his chin on the back of her head and crawling over her. When she is willing, she raises her tail. At that point, he wraps his tail around hers so the bottoms of their tails meet at the cloaca -- the exit point for waste and reproductive fluid. The male inserts his two sex organs, the hemipenes, which then extend and release sperm. Snake sex usually takes under an hour, but it can last as long as a whole day.
Female snakes reproduce about once or twice a year; however, the methods of birth vary among species. Some snakes give birth to live young (from one to 150 at a time), while others lay eggs (from one to 100 at a time); some even combine these methods by holding eggs internally until they hatch, and the babies are born live. For the most part, female snakes do not sit on their eggs like a hen, but in some cases they will protect their eggs (and their young) for a few days after they leave the mother's body.
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