Yesterday (27th July), an item was posted on telegraph.co.uk titled ‘Germaine Greer: Snails deserve our attention’.
‘… A wet summer has brought Britain’s snail population out in force. These enigmatic creatures deserve closer attention, and even a little tenderness …
This is the year of the snail. My one-acre wood is festooned with them: garden snails, banded snails and even, I think, “Kentish” snails or Monacha cantiana. There will be readers of these words whose blood runs cold when they realise that, no matter how many snails they put to death, there are billions more making the best of this summer’s dark skies and warm rain.
Every year, as soon as we have a spell of dull, humid weather, we are told that there are unprecedented numbers of snails about. In fact the level of the mollusc population, year by year, is a good deal more constant than that of the insect population.
Snails don’t travel far; although I may have seen more snails this year, I probably harbour about the same number as usual. In less sodden years, snails sleep through the summer days and go grazing at night; this year they have been on the move around the clock.
Snails need calcareous soil; some species can even eat limestone. Most of our native species are survivors of the woodlands that once covered these islands. If they are in your garden now, it is because they have no choice. In woodland it is easier to see how necessary they are to the recycling of rotting plant material. Right now, in my wood, snails of all sizes are hauling themselves up the trees. As they climb, the tiny denticles on their radulas, which are rather like power-driven sanding blocks set in their mouths, are constantly scraping off the algal moulds that have formed on almost every branch.
I wish I could tell you how the snail converts this unpromising material into nutriment; it’s just another of the many things we don’t know about a fellow Earthling we see every day. Many people find snails repulsive, but to see a big old garden snail hoisting itself up a tree like a Winnebago climbing stairs is oddly moving: and never more so than when a juvenile snail of another species has hitched a ride on its shell. A snail crawling up a window blind has been shown to be able to hoist 51 times its own weight. Snails represent an extraordinary combination of great strength with utter gentleness …
Snails are deaf, so you can’t train them to carry out orders; but they are capable of associative thinking. They can remember where things are; they know where they sleep; Darwin noticed how one snail discovered how to escape from a tank, and returned the next night to help another snail escape by the same route.
They do not have brains as such. The cell bodies of their nerve cells are concentrated in a set of ganglia. Because mollusc nerves have no insulating myelin sheath, snails have developed long nerve fibres called axons to enable fast transport of impulses. Such snail axons are being used in attempts to make “semi-alive” microchips for treating problems related to defective brain function in humans, such as some forms of blindness. (The next time you want to stomp on a snail, just fire up your own neurons and go figure.)
Snails can express satisfaction and dejection by the way they move their tentacles: two long ones for seeing, two short ones for smelling. When American author Elisabeth Tova Bailey was paralysed and kept helpless and flat on her back by a mysterious disease, she was greatly aided in fighting off despair by the quiet routines of a snail that had come into her sickroom as a stowaway in a plant pot. In her now famous book, The Sound of a Wild Snail Eating, she describes how she got to know and respect her snail.
This was by no means the first time these magical molluscs have teased a writer’s curiosity. Shakespeare twice refers to “the tender horns of cockled snails” and the way a frightened snail “Shrinks backwards in his shelly cave with pain”. His disciple Keats latched on to the “tender horn” with the same oxymoronic idea …
The reality is that nothing is more mutual than snail mating: each hermaphrodite snail has to arouse another hermaphrodite snail, and then move in perfect synchrony towards mutual ejaculation. Each snail has a dart that inserts a spermatophore in its sexual partner, and an organ that receives the partner’s sperm. Their mating is entirely reciprocal, with intromission occurring simultaneously. So complex are these arrangements that they account for most of the snail’s anatomy.
There is a lot of variation from one species to another, but as a general rule this process happens around once a month. But snails are promiscuous, and can store sperm from a number of partners for several years.
After mating, each snail will lay about 100 eggs, supplying each with its own calcium shell which is the beginning of the shell of the born snail. Most of the hatchlings will be eaten by a vast range of predators, including other snails. As creatures near the bottom of the food chain, snails are necessary beings. There is hardly a bird that will not eat a snail; badgers, foxes, snakes, blindworms, hedgehogs, moles, shrews, toads, frogs, ground beetles, fireflies, harvestmen, all willingly eat snails.
Humans eat snails too, which is why we have the brown garden snail which is apparently native to the western Mediterranean. It used to be called Helix aspersa, but the gradual realisation that its reproductive apparatus is quite unlike that of other Helix species has caused it to be removed from that genus. It can’t be said reliably to have entered any other, so for the time being it is known as Cornu aspersum.
Other names have been suggested: Cantareus (the singing snail), maybe; or Cryptomphalos (the hidden navel). But – at least until another member comes along – Cornu remains, quite literally, sui generis …’
Read the item in full and add your comment online at www.telegraph.co.uk/lifestyle/9433231/Germaine-Greer-Snails-deserve-our-attention.html