Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Unravelling The Ecology Of Snail Shell Coiling

01.09.2003


Ecologists are taking to the trees in a bid to unravel the ecology of shell coiling in snails. Speaking at the British Ecological Society’s Annual Meeting, being held at Manchester Metropolitan University on 9-11 September 2003, Dr Paul Craze of the University of Plymouth will explain how examining the proportion of right- and left-coiling individuals in a species of Bornean tree snail could help ecologists understand how new species arise.



The vast majority of snail species are almost exclusively dextral, or right-coilers, with just the occasional sinistral, or left-coiling, individual. However, in a small number of snail species there appears to be a stable balance between the number of right- and left-coilers. Coil direction in snails is inherited from the mother and is controlled by a single genetic locus or region, and coil direction is important because it is difficult for right-coiling snails to mate with left-coiling snails.

The fact that left- and right-coiling snails cannot align themselves properly during mating is, however, more than an irritation to the snails and an interesting puzzle for ecologists. Understanding how new species arise is a fundamental biological problem, and in the case of snails, some ecologists believe that the existence of left- and right-coiling individuals could be one mechanism for sympatric speciation (the development of new species by isolating them other than geographically). Since left-coiling and right-coiling snails find it hard to mate with each other they may, over time, develop into separate species.


Dr Craze and Dr Menno Schilthuizen of the Universiti Malaysia Sabah studied shell coiling in Amphidromus martensii, a snail that lives in the rainforests of Borneo, and one of the few species that is composed of roughly 50% right- and 50% left-coiling individuals, to find out what factors are responsible for maintaining this 50:50 split, and whether or not the right- and left-coilers show evidence of diverging towards becoming different species.

“There has been virtually no ecological study of shell-coiling polymorphism, so the first thing we were interested in was whether the 50:50 ratio that we know exists at the medium scale (ie between sites separated by tens of kilometres) also exists at a smaller scale (ie between sites separated by tens of metres), or whether the right coilers occupied different habitats from the left coilers,” Dr Craze says.

Because A. martensii lives in the forest canopy, Dr Craze chose to collect shells of dead snails from the ground. “We found equal numbers of left and right coilers no matter what scale we chose, which suggests that we are dealing with a truly balanced polymorphism and that these snails are not at the early stages of speciation. If that turns out to be the case, we need to identify what factors are responsible for keeping the polymorphism so balanced,” Dr Craze explains.

However, to make sure that the results they have found are not only confined to snail shells found on the ground, Dr Craze will be repeating the experiment by hanging from a rope in the rainforest looking at live snails in the forest canopy. “We also plan to use small snail-sized radio transmitters to track movements of snails to see how many snails of each coil-type an individual is likely to encounter and so work out the potential for gene flow between areas,” he says.

According to Dr Craze: “Our work may have some interesting implications. Studies of the ecological factors responsible for maintaining balanced polymorphism are still quite rare. On the other hand, if some degree of divergence between the coil-types is discovered, we have a model system for studying what may be an interesting mechanism of sympatric speciation.”

Dr Craze will present his full findings at 15:00 on Tuesday 9 September 2003.

Becky Allen | alfa
Further information:
http://www.britishecologicalsociety.org/

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>