Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Evolution At A Snail’s Pace

05.07.2004


Littorina saxatilis


Most visitors to the seaside are content to ride donkeys, eat ice cream, and build sandcastles. But, University of Leeds scientists have no time for sunbathing; they are witnessing the birth of a new species on the rocky shores of North Yorkshire.

Littorina saxatilis (right) is an unremarkable rough periwinkle – a small, grey-brown sea-snail which litters the coast by the million. But it has overcome its lack of charisma and grabbed the attention of scientists trying to unlock the secrets of evolution.

Biologist John Grahame (left) said: “This is an example of evolution in action, and we are increasingly certain that we are seeing one species become two.”



Evolution is a slow business at the best of times, and the process of speciation – the division of one species into two – takes millennia. The best scientists can hope to see is that two forms or ‘morphs’ within a species are moving apart, and becoming genetically distinct.

Down on beaches at Flamborough, Filey Brigg and Ravenscar, Dr Grahame and colleagues have shown that there are two distinct morphs of L. saxatilis inhabiting different parts of the beach, and the basis for the difference is genetic.

The really exciting development – the holy grail of speciation – is evidence that the morphs are becoming reproductively isolated and no longer freely interbreeding. Individual snails prefer to mate with others of the same morph, and when interbreeding does happen, the viability of the young is reduced.

“There are alternative explanations”, says Dr. Grahame, “and the process could easily be reversed. The point of no return, when we can truly say a new species has been born, will come when there is no interbreeding at all, and no gene flow between the morphs.”

The researchers are currently analysing genetic differences between morphs, and aim to relate the DNA sequence differences to physical characteristics.

Rough periwinkles are a favourite food of crabs, and it is likely that the two morphs use different strategies to stay off the menu. Crab ‘resistors’ are the thick shelled morph, found low on the beach where crabs are common, while thin shelled crab ‘avoiders’ are found higher up the shore.

This shows remarkable similarity to the evolutionary history of other periwinkles, such as the flat periwinkle species found in our waters, one of which is a crab avoider, the other a crab resistor. Dr. Grahame believes Littorina saxatillis is following slowly in their footsteps.

Vanessa Bridge | alfa
Further information:
http://www.leeds.ac.uk
http://reporter.leeds.ac.uk/500/s1.htm

More articles from Life Sciences:

nachricht Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg

nachricht The balancing act: An enzyme that links endocytosis to membrane recycling
07.12.2016 | National Centre for Biological Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Silicon solar cell of ISFH yields 25% efficiency with passivating POLO contacts

08.12.2016 | Power and Electrical Engineering

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>