RIP Jeremy the snail
Our one-in-a-million 'lefty' snail Jeremy, who achieved international notoriety after scientists launched a public appeal to find him a mate, has died. However, the sad news comes with a bittersweet twist to the tale – our lonely mollusc finally found love, mating with another 'lefty' snail shortly before his death and producing offspring, ensuring that his legacy will live on through continuing genetic studies into his rare mutation.
Jeremy was found dead on 11 October by his scientist, Dr Angus Davison in the University's School of Life Sciences.
"Although it is unfortunate that Jeremy has gone, the help that we have received from the public to find more lefty snails has been amazing," said Dr Davison. "Because of the rarity of lefty garden snails, we have never before been able to get two lefty snails together to study the inheritance of the condition. Through the appeal on BBC Radio 4, which then went out worldwide, we ended up finding six other lefty snails.
"This may be the end for Jeremy, but now the snail has finally produced offspring, this is a way point in our long term research goal to understand the genetics of body asymmetry. Ultimately, we would like to know why these snails are so rare, but also how the left and right sides of the body are signalled at the molecular level, and whether a similar process is taking place during human development."
A rare discovery
Jeremy was discovered around a compost heap in South West London by a retired scientist from the Natural History Museum, who contacted Dr Davison after hearing about his interest in snail genetics.
Dr Davison – who had never before seen a sinistral brown garden snail in 20 years of working with the creatures – was keen to discover whether the mutation was the result of genetic inheritance or a quirk in development.
Offspring from Jeremy may offer valuable insights into a common understanding of body asymmetry in other animals, including humans.
Sadly however, Jeremy's unique traits were not confined to his shell. The condition features the reversal of other major organs – including the genitals – meaning that he was unable to successfully mate with the more common variety of dextral garden snails with shells that coil in a clockwise direction.
The slither of tiny feet
Happily, shortly before Jeremy's death was discovered, his lefty beau Tomeu produced a batch of 56 babies – about one-third of which are likely to be 'fathered' by Jeremy. The remainder will be the result of an earlier liaison with Lefty, another suitor found for Jeremy.
Jeremy's offspring have all been born with right coiling shells, providing that in the case of these rare mutant snails, two lefts make a right – at least in the second generation.
The fact that the babies developed right-coiling shells may be because the mother carries both the dominant and recessive versions of the genes that determine shell-coiling direction. Body asymmetry in snails is inherited in a similar way to bird shell colour – just as only the mother's genes determine the colour of a bird egg, only the mother's genes determine the direction of the twist of a snail shell. It is far more likely that left-coiling babies will be produced in the next generation or even the generation after that.
Last year, in research published in the journal Current Biology, Dr Davison and colleagues at universities in Edinburgh, Germany and the US, revealed they had discovered a gene that determines whether a snail's shell twists in a clockwise or anti-clockwise direction.
The same gene also affects body asymmetry in other animals – including humans – and research using these snails could offer the chance to develop our understanding of how organs are placed in the body and why this process can sometime go wrong when some or all of the major internal organs are reversed from their normal placement.
Jeremy's shell has been preserved for the University's natural history collection and will be used to teach students about this rare genetic variant.