Snails

Snails are diversified in two catagories land snail and water snails. All land snails are hermaphrodites, producing both spermatozoa and ova. Some aquatic snails, such as Apple Snails, are either male or female. Prior to reproduction, most snails will perform a ritual courtship before mating. This may last anywhere between two and twelve hours. Prolific breeders, snails inseminate each other in pairs to internally fertilize their ova. Each brood may consist of up to 100 eggs.Snails have small slits on their necks where fertilization occurs and the eggs develop. Garden snails bury their eggs in shallow topsoil primarily while the weather is warm and damp, usually 5 to 10 cm down, digging with their 'foot'- the back of their 'tail'. Egg sizes differ between species, from a 3 mm diameter in the grove snail to a 6 cm diameter in the Giant African Land Snail. After 2 to 4 weeks of favorable weather, these eggs hatch and the young emerge. Snails may lay eggs as often as once a month. The snail's shell develops while it is still an embryo; it is, however, very weak, and they need an immediate supply of calcium. Newly hatched snails obtain this by eating the egg they hatched out of. Baby snails cannibalizing other eggs, even unhatched ones, has been recorded. Promptly after they are finished ingesting their egg casings, they crawl upwards through the small tunnel left from their parent digging their nest. At this stage, the young are almost completely transparent. Their shell is usually slightly smaller than the egg they hatched from, but their body length when out of their shell is slightly greater than the egg diameter. After a few weeks, the snails will begin to gain their first tinging, usually slightly blue before they turn their adult color. In roughly three months after they have hatched, they will look like miniature versions of their mature kin. They will continue to grow, usually for two to three years until they reach adult size, although there have been confirmed recordings of snails growing amazingly fast - even bigger than their parents in little more than a month[citation needed]. Irrespective of their rate of growth, it will still take 2 to 6 years before they are sexually mature. There have been hybridizations of snails; although these do not occur commonly in the wild, in captivity then can be coaxed into doing so. Parthenogenesis has also been noted in certain species. Pond snails do not lay their eggs in the ground but carry them around until they hatch.