... what's really going on in your garden ... ewww !
Snail sex. No, this is not about some weird sexual slow-breathing palaver for humans. It’s about sex, snail style. Snails, as in molluscs. Slimy, icky little molluscs ... ew ... but I digress.
The common garden snail, Helia aspersa (native to Europe and also found in California and South America), is a hermaphrodite, meaning that it can assume either a male or female role in reproduction as required. (Yes, of course this story gets better).
Garden snails court from between 15 minutes to six hours by slowly circling each other, touching tentacles, and biting each others lips and genitalia. They punctuate their mating ritual by shooting their partners with a calcified ‘love dart’ produced by the blood engorgement of a special organ housing the ‘dart’.
When the partner touches the ‘darter's’ genitalia, a 'dart' is fired. Now, as snails can detect light and dark, but are otherwise ‘blind’, it is a real case of hit and ms. (pardon my pun). In fact, the majority of these ‘darts’ are consumed (eaten) by the ‘female’ of the union.
Biologists have proven that a 'signal' carried only on some darts prevents the mate from digesting them. The female reproductive tract in snails is hostile to sperm by design, to make it difficult for ‘weak’ sperm to survive, so only the strongest ‘darts’, with their powerful chemical beacon, will survive undigested and fertilise the ‘female’.
Unless the ‘female’ gets a ‘signal’ from the dart, she will digest 99.98 percent of the ‘males’ sperm, leaving fertilisation from ‘poor quality’ sperm a near impossibility.
Wow. Do these snails have genetic survival nailed or what ? 
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