Social sunbathing in the mint-sauce worm

February 23, 2016
Self-organizing social behavior in the so-called plant-animal, a 'solar-powered' species of marine flat worm that gains all its energy from the algae within its own body, has been demonstrated by researchers from the University of Bristol, UK. Commonly known as the 'mint-sauce worm' due to its bright-green color, S. roscoffensis is found in shallow water on sheltered sand beaches at certain sites on the Atlantic Coast. Credit: © Professor Nigel Franks

Self-organizing social behaviour in the so-called plant-animal, a 'solar-powered' species of marine flat worm that gains all its energy from the algae within its own body, has been demonstrated by researchers from the University of Bristol, UK.

Professor Nigel Franks in the School of Biological Sciences and colleagues, especially Dr Alan Worley, formerly of the School of Physics, made direct comparisons between videos of the real and computer simulations of virtual worms with different patterns of behaviour. This showed that individual plant-animal worms (Symsagittifera roscoffensis) interact with one another to coordinate their movements.

Commonly known as the 'mint-sauce worm' due to its bright-green colour, S. roscoffensis is found in shallow water on sheltered sand beaches at certain sites on the Atlantic Coast, including the coasts of Wales and the Channel Islands. Adult worms survive entirely on the nutrients produced by photosynthesizing symbiotic algae living in their bodies, hence their renown as the 'plant-animal'.

These 3mm-long worms sunbathe on beaches when the tide is out and bury themselves in the sand as the sea returns. The Bristol study shows how with increasing density they form small flotillas, and then circular mills. The authors hypothesize that these interactions eventually lead to the mat-like biofilms observed on sandy beaches. These social structures may help the worms to achieve safety in numbers and the right conditions for their unusual way of life.

Professor Franks said: "Such social behaviour helps the worms to form the dense biofilms that have been observed on certain sun-exposed sandy of the East Atlantic, and to become in effect a super-organismic seaweed in a habitat where macro-algal seaweeds cannot anchor themselves."

Symsagittifera roscoffensis is a 'model organism' in many areas in biology (including ) but its has been comparatively neglected.

"Our study suggests this remarkable organism also seems to be an ideal model for understanding how individual behaviours can lead, through collective movement, to social assemblages," Professor Franks added.

The research is published today in Proceedings of the Royal Society B.

Explore further: Worms use immune system to extract food from cells

More information: Social Behaviour and Collective Motion in Plant-Animal Worms, Proceedings of the Royal Society B: Biological Sciences, rspb.royalsocietypublishing.or … .1098/rspb.2015.2946

Related Stories

Worms use immune system to extract food from cells

February 16, 2016

White blood cells are usually our allies in fighting infections, but new research shows that when Trichinella worms first invade muscle cells, one particular type of white blood cell doesn't attack – rather it helps the ...

Exploring the genomic basis of parasitism

February 2, 2016

The genes that cause parasitism in a group of intestinal worms, responsible for one of most prevalent tropical diseases in the developing world, have been identified by an international team of scientists, led by the University ...

Mystery of 'zombie worm' development unveiled

March 12, 2013

How do bone-eating worms reproduce? A new study by Norio Miyamoto and colleagues from the Japan Agency for Marine-Earth Science and Technology sheds light on this question through a detailed observation of the postembryonic ...

Watching sensory information translate into behavior

February 12, 2016

It remains one of the most fundamental questions in neuroscience: How does the flood of sensory information—everything an animal touches, tastes, smells, sees, and hears—translate into behavior?

Recommended for you

Novel framework to infer microbial interactions

December 11, 2017

Inferring the underlying ecological networks of microbial communities is important to understanding their structure and responses to external stimuli. But it can be very challenging to make accurate network inferences. In ...

Yeast can be engineered to create protein pharmaceuticals

December 11, 2017

It took several years, but a research team headed by Professor Jens Nielsen at Chalmers University of Technology has finally succeeded in mapping out the complex metabolism of yeast cells. The breakthrough, recently published ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.