![]() Jeremy the left-coiling snail on top of Bree, a right-coiling snail. | |
Species | Cornu aspersum |
---|---|
Breed | Sinistral |
Sex | Hermaphrodite |
Hatched | London, UK |
Died | 11 October 2017 [1] |
Owner | University of Nottingham |
Residence | United Kingdom |
Offspring | 56 |
Appearance | Left-coiled |
Named after | Jeremy Corbyn |
Jeremy was a left-coiled garden snail investigated by biologists. The snail had a rare condition that caused its shell to coil to the left; in most snails the shell coils to the right. At first it was thought to be a rare genetic mutation, [2] although later work revealed that it was likely due to an accident in early development. [3]
Jeremy was named after the left-wing British Labour politician Jeremy Corbyn, on account of it being a "lefty" snail, but also due to Corbyn's reported love of gardening. [4] [5] [6] The snail became famous worldwide after a public appeal to find other left-coiled snails for a mate. [7] [8] Jeremy had 56 offspring and died on 11 October 2017, aged "at least two" years. [1]
Jeremy was studied by researchers from the University of Nottingham. It was hoped that the condition would be due to a mutation, and that genes identified from this snail and its offspring would help scientists unlock genetic markers in humans and other animals. [9]
A retired scientist found Jeremy in southwest London. He contacted the University of Nottingham and sent them the snail. A group of researchers, led by "resident snail expert" Dr Angus Davison, then launched a public appeal to find another 'lefty' snail as a mate. [10] Due to the unique positioning of the reproductive body parts in anticlockwise-coiled snails, they are only able to mate with snails that also have anticlockwise shells. [11] [12] Two other anticlockwise snails were discovered and sent to the university; [13] however, these two snails mated with each other instead, producing 170 right-coiled snails. [14] One of the left-coiled snails later mated with Jeremy, producing 56 offspring, all of which also had right-coiling shells. [15]
It is believed that the genetic mutation might reappear in a later generation due to a recessive gene. [16] [17] In snails, shell-coiling direction is thought to be an example of a maternal effect – a trait that is determined not by an organism's own genotype, but by the genotype of its mother. In this case, Jeremy's mother (who likely possessed a right-coiling, or clockwise, shell), would have had two copies of the recessive gene, expressed in Jeremy's anticlockwise shell. Jeremy, with only one copy of the gene, would be expected to mother snails with right-coiling shells. This recessive trait may reappear later in another generation, even if a previous generation appears to have right-coiling shells, because the mutation is hereditary. [18] [19]
While studying this snail, Davison discovered a gene that determined whether a snail's shell coiled to the left or to the right. He said that body asymmetry in humans and other animals could be affected by the same gene and that the research could help understand the positioning of organs according to genetic markers. [20] [21]
Davison was quoted as saying:
This may be the end for Jeremy, but now the snail has finally produced offspring, this is a point in our long-term research goal. 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. [22]
Research was expected to continue on the offspring of these snails, and the University of Nottingham had seven left-coiled snails by October 2017. [23]
In July 2018, the research team at the University of Nottingham announced the arrival of St Stephen, a 'lefty' snail of the species Cepaea nemoralis and stated in a tweet that they were looking for potential mates. [24]
It was hoped that this research will lead to insights into rare conditions like situs inversus and situs ambiguus where the positioning of organs in the body is reversed or misplaced due to genetic malformations. [25] [26] [27]
Jeremy was an example of a rare sinistral snail in a species that usually has right-handed shell-coiling. [28] Such snail kings are individual snails whose shell winds in the opposite direction given the standard for the specific snail species. [29] For instance, in the case of garden snails, snail kings feature sinistral helices instead of the more common dextral helices; this is referred to as 'situs inversus'. [30] For garden snails, researchers estimate the occurrence frequency of snail kings at 1:40,000 individuals. [3] However, in some other species of snail, the counterclockwise shell-coiling is quite common, and in a few cases counterclockwise shell coiling is the right-hand (clockwise) direction. [31] [32]
Snail kings may occur after the mating of two dextral helix snails (with the offspring of these snails continuing to be sinistral) and are therefore considered to be a highly illustrative example that heredity patterns are not purely dominant-recessive. [33]
Gastropods, commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda.
Disassortative mating is a mating pattern in which individuals with dissimilar phenotypes mate with one another more frequently than would be expected under random mating. Disassortative mating reduces the mean genetic similarities within the population and produces a greater number of heterozygotes. The pattern is character specific, but does not affect allele frequencies. This nonrandom mating pattern will result in deviation from the Hardy-Weinberg principle.
Situs inversus is a congenital condition in which the major visceral organs are reversed or mirrored from their normal positions. The normal arrangement of internal organs is known as situs solitus. Although cardiac problems are more common, many people with situs inversus have no medical symptoms or complications resulting from the condition, and until the advent of modern medicine, it was usually undiagnosed.
Sinistral and dextral, in some scientific fields, are the two types of chirality ("handedness") or relative direction. The terms are derived from the Latin words for "left" (sinister) and "right" (dexter). Other disciplines use different terms or simply use left and right.
Busycotypus canaliculatus, commonly known as the channeled whelk, is a very large predatory sea snail, a marine prosobranch gastropod, a busycon whelk, belonging to the family Busyconidae.
Dakshinavarti shankha, also referred to as Valampuri shankhu and Sri Lakshmi shankha is a sacred Hindu conch. It refers to the shell of a large sea snail from the Indian Ocean, but one that has a rare reverse-turning spiral.
The gastropod shell is part of the body of a gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or in some cases the shell is reduced such that the body cannot be retracted within it (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group.
Planorbidae, common name the ramshorn snails or ram's horn snails, is a family of air-breathing freshwater snails, aquatic pulmonate gastropod molluscs. Unlike most molluscs, the blood of ram's horn snails contains iron-based hemoglobin instead of copper-based hemocyanin. As a result, planorbids are able to breathe oxygen more efficiently than other molluscs. The presence of hemoglobin gives the body a reddish colour. This is especially apparent in albino animals.
Planorbarius corneus, common name the great ramshorn, is a relatively large species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails, or planorbids, which all have sinistral or left-coiling shells.
Segmentina nitida, the shining ram's-horn snail, is a species of minute, air-breathing, freshwater snail, an aquatic gastropod mollusc or micromollusc in the family Planorbidae, the ramshorn snails.
Euhadra is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the subfamily Bradybaeninae of the family Camaenidae.
Sinistrofulgur perversum, the lightning whelk, is a species of very large predatory sea snail or whelk, a marine gastropod mollusc in the family Busyconidae, the busycon whelks. This species has a left-handed or sinistral shell. It eats mostly bivalves.
Iwasaki's snail-eater is a species of snake in the family Pareidae. The species is endemic to the Yaeyama Islands in the southern Ryukyu Islands, Japan.
Amphidromus is a genus of tropical air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Camaenidae. The shells of Amphidromus are relatively large, from 25 mm (0.98 in) to 75 mm (3.0 in) in maximum dimension, and particularly colorful. During the 18th century, they were among the first Indonesian land snail shells brought to Europe by travelers and explorers. Since then, the genus has been extensively studied: several comprehensive monographs and catalogs were authored by naturalists and zoologists during the time period from the early 19th to the mid 20th centuries. Modern studies have focused on better understanding the evolutionary relationships within the group, as well as solving taxonomic problems.
Turbinella pyrum, common names the chank shell, sacred chank or chank, also known as the divine conch or referred to simply as a conch, is a species of very large sea snail with a gill and an operculum, a marine gastropod mollusk in the family Turbinellidae. This species occurs in the Indian Ocean.
Amphidromus inversus is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Camaenidae.
Chirality is a property of asymmetry important in several branches of science. The word chirality is derived from the Greek χείρ (kheir), "hand", a familiar chiral object.
Ayna is a monotypic genus of air-breathing land snails, terrestrial gastropod mollusks in the family Enidae. The sole species in the genus is Ayna mienisi. It was described as Zebrina (Ramusculus) mienisi. The genus Ramusculus however is a monotypic genus only distantly related to Ayna. The closest relative of Ayna is probably Clausilioides.
Pareidae is a small family of snakes found largely in southeast Asia, with an isolated subfamily endemic to southwestern India. It encompasses 42 species in four genera divided into two subfamilies: Pareinae and Xylophiinae. Both families are thought to have diverged from one another during the early-mid Eocene, about 40-50 million years ago.
In developmental biology, left-right asymmetry is the process in early embryonic development that breaks the normal symmetry in the bilateral embryo. In vertebrates, left-right asymmetry is established early in development at a structure called the left-right organizer and leads to activation of different signalling pathways on the left and right of the embryo. This in turn causes several organs in adults to develop LR asymmetry, such as the tilt of the heart, the different number of lung lobes on each side of the body, and the position of the stomach and spleen on the right side of the body. If this process does not occur correctly in humans it can result in heterotaxy or situs inversus.
The university said it could not be sure of Jeremy's exact age but he was 'at least two'.