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Nature’s Web Newsletter – Summer 2012
The Summer 2012 Issue of the Nature’s Web Newsletter, an exciting newsletter for children, has been posted on the web.

In this issue you’ll find…

The Joy of Fishing!
Editor’s Page: For the Love of Birds
Bird Life: The Swift
Aquatic Life: Sticking Around – The Wonderful World of Barnacles
Animal Life: Pygmy Shrew
Plant Life: Choking the Waterways
All in a Day’s Work: Mark Corps, Angling Advisor, Inland Fisheries Ireland
Colour In: Fun Catch!
Wordsearch: Nature’s Web Spring 2012
Learn More: Books/DVD for children
The World Around Us: “Foreign Correspondent” Michael Ludwig
Activity: Play Acting!
Fun Page: How Much Did You Learn?, Nature Jokes
Conservation: A River in Summer
Special Feature: Angling for Children
Nature’s Noticeboard

Pages are in pdf format (Adobe Reader). You can download each page individually, or the whole newsletter in one go.

Hope you enjoy it!

The newsletter is produced by Sherkin Island Marine Station, Sherkin Island, Co. Cork, Ireland.

A history of Ireland in 100 objects : On the morning of July 14th, 1690, King William III presented these fine doeskin gloves to John Dillon, in whose home in Lismullin, Co Meath, he had stayed the previous night. The king had reason to be in a buoyant mood: he had won a major victory over his rival King James II at the nearby River Boyne two days previously.

Gloves were often given as presents, but there is reason to think that William may actually have worn these at the battle, in which he personally commanded the cavalry. The elaborate gold lace border on the right glove is worn away, and the left glove shows signs of heavy use. If Protestants believed in relics, these remnants of the ultimate hero in his finest hour would surely be holy.

The battle may be the most famous in Irish history, but it was shaped by two events beyond Ireland. One was the succession to the English throne of James II. He alienated parliament and the nobility by his conversion to Catholicism and insistence on the absolute rights of the monarchy. The other event was the French king Louis XIV’s invasion of the Rhenish Palatinate and the Netherlands. William of Orange emerged as a key figure in the broad anti-French front that emerged in response. These two questions became one when William, who was James’s nephew and son-in-law, arrived in England in November 1688, with 15,000 troops. He and his wife, James’s daughter Mary, were crowned king and queen.

James landed in Kinsale in March 1689. His forces failed to establish complete control of the island, with Derry heroically withstanding a siege from April until its relief in August. William followed James to Ireland and hoped for a single decisive battle. The Battle of the Boyne, with 36,000 troops on William’s side and 25,000 on James’s, was indeed the largest ever fought on Irish soil. It was a pan-European affair, with soldiers from the Netherlands, Denmark, Germany, Norway and Poland, as well as from Britain and Ireland. Frenchmen fought on both sides, with some Hugenot Protestants fighting for William and an army of 6,500 men sent by Louis supporting James.

The decisive action was at the village of Oldbridge. William’s flanking manoeuvres drew off most of the Jacobite army, leaving a rump, outnumbered three to one, to face the main attack. The fighting nevertheless lasted for 12 hours, and William’s hopes of catching the Jacobites in a pincer movement were dashed. James was able to retreat westwards with the bulk of his army. He escaped to France via Dublin and Cork; most of his Irish army fought on.

In that regard, the Boyne was not decisive: the Battle of Aughrim, in July 1691, was far bloodier and more conclusive. Nor was it the simple sectarian triumph of subsequent legend: William’s shock troops, the Dutch Blue Guard, were Catholic, and his allies included the Vatican and Vienna, where Te Deums were sung to celebrate the Boyne victory. Conversely, much of the Protestant hierarchy remained loyal to James. But the personal presence of the two kings gave the Boyne a mythic power that turned it into the ultimate Protestant triumph.

Thanks to Alex Ward

Where to see it National Museum of Ireland – Decorative Arts History, Collins Barracks, Benburb Street, Dublin 7, 01-6777444, museum.ie 

CLAIRE O’CONNELL

SMALL PRINT: WHAT’S in an octopus? Not just brains to burn, but also significant new clues that could justify concerns about climate change.

Recent research in the Southern Ocean, involving scientific input from NUI Galway’s Ryan Institute (NUIG), has found that populations of the Turquet’s octopus (pictured) living on either side of the Western Antarctic ice sheet share almost identical genes.

On balance, this shouldn’t make any sense, given that the adult octopuses, named after a French biologist, are known to be territorial creatures which only tend to move under pressure from predators. And the Ross and Weddell seas, the locations for the population study, are 10,000 km apart.

However, the vast frozen territory that separates them is one of the world’s three major ice sheets, and has been identified as the most vulnerable to climate change. Should it collapse, it could cause a serious rise in sea levels.

Dr Louise Allcock of NUIG’s Ryan Institute, who has been visiting Antarctica on research since 1994, participated in the study with colleagues from Liverpool and Australia’s La Trobe universities. She says the genetic link supports the theory that the Ross and Weddell seas were once all one, due to the ice sheet’s collapse.

Previous modelling studies relating to climate change had suggested evidence of a sea link between Ross and Weddell, Dr Allcock says. “However, due to the lack of samples, it was very unclear. Now, this is the first genetic proof. It also provides further evidence that scientists should continue to raise awareness about the impact of climate change on Antarctica today.”

“We’ll continue to do the research, as the Turquet’s octopus is proving to be a really good model,” she explains. “Not moving at all at any stage in your life tends – for marine species – to be very rare.”

The team’s research, published in the journal Molecular Ecology, was supported by the British Natural Environment Research Council and the Collaborative Scheme for Systematic Research.

The countdown to the London 2012 Games began in earnest today as the world watched the Olympic Flame being lit in ancient Olympia.

The traditional ceremony took place under baking sun and tight security in front of the ruins of the Temple of Hera in Greece, birthplace of the ancient Games.

Dressed in robes, Ino Menegaki, an actress who has studied classical song, music and movement, played the key role of the high priestess who lights the flame from the rays of the sun.

She lifted a blazing torch from a parabolic mirror so it is lit as if beamed by the sun’s rays from the Greek god of the sun to guarantee the purity of the flame, according to tradition.

This is the only way the Olympic flame can be lit, again as stated by ancient rituals.

The torch for the London Games will set off on a seven-day journey across Greece before it leaves for Britain on May 18th.

A Traveller, a special Olympian and a garda will join six Irish Olympic medallists from the last half century in the Dublin relay of the torch next month.

The relay will inspire a generation and lift the spirits of people in Britain and the world, Games chief Sebastian Coe said today at the lighting ceremony.

“We promise to protect the Flame; to cherish its traditions and to stage an uplifting torch relay of which we can all be proud and which can inspire a generation,” Mr Coe said in his brief speech in front of the International Olympic Committee president Jacques Rogge.

“As torchbearers lift the Olympic flame in the days and months ahead, it is our hope that they will also lift the spirits and hopes of people across Britain and across world,” said the former Olympic champion.

“We will involve young people from all backgrounds, cultures and faith groups in the torch relay, reflecting London’s immense diversity and creativity as a global destination and voice for young people,” said Mr Coe.

“This is the second time the people of the UK have gathered here to celebrate igniting of the flame,” he said.

“In 1948, shortly after the Second World War, my predecessor stood where I am today and made the first tentative steps in turning the world from war to sport.”

“We find ourselves in challenging times again and turn to sport once more to connect the world in a global celebration of achievement and inspiration.”

London is the only city to have lit the torch twice in Olympia.

The 70-day torch relay will travel 12,800 km around Britain, taking in 1,018 villages and the 1,085-metre summit of Snowdon, before culminating with the lighting of the Olympic cauldron in the Olympic Stadium on the opening day of the Games on July 27th.

The relay will also take in landmarks around Britain with the flame travelling by canal boat, cable car, tram, steam train, hot air balloon and even motorcycle sidecar on the Isle of Man TT course.

More than 95 per cent of the population will be within an hour of the route.

Among the 41 torch bearers to carry the flame in Dublin are Eurovision duo Jedward (John and Edward Grimes) who will carry it together. The pair are keen cross-country runners and completed the Los Angeles marathon in March.

A detail from Desmond Kinney’s 1974 Táin Wall off Nassau Street in Dublin depicting Cúchulainn and Ferdia in single combat. New DNA technology means Irish people can trace their ancestry and while they obviously cannot trace a lineage to legendary heroes, the process can identify links to ancient royal Irish families.

WHOSE BLOOD courses through your veins? Could you be a descendant of a Viking warrior or a Berber pirate? Or perhaps you are related to the Uí Neill chieftains or the kings of Laighin (Leinster)?

If so your genes will carry the proof, and a new company set up by scientists offers a service that can reveal your genetic heritage.

Today sees the launch of “Ireland’s DNA”, a direct to customer genetic ancestry service. “We are planning it as a national project. The more people that get involved, the more we can understand about Irish history from the resulting dataset,” says Dr Gianpiero Cavalleri, one of three founders of the company.

Cavalleri is a biomedical research lecturer at the Royal College of Surgeons in Ireland and heads its epilepsy genetics group. The Irish project grew out of a similar undertaking that started about six months ago in Scotland.

And that in turn came out of a book examining the genetic ancestry of Scotland, The Scots: A Genetic Journey. The authors were Dr James Wilson, a geneticist at the University of Edinburgh who works on the genetic roots of disease, and historian Alistair Moffat.

“There was huge public interest in the book,” Dr Cavalleri says, so much so that the three decided to set up a company, Scotland’s DNA, to help finance further study of the country’s collective genome.

“Now we are going to use the same concept for Ireland,” he says. He got the idea some years ago while at Stanford University. He became fascinated with the idea that you could identify past human migration by looking at the male-only part of the genome, the Y chromosome.

As males of a given lineage began their migration out of Africa, some would have been more successful than others. Untold numbers would have been killed off, but many continued to branch out into Europe and Asia. Successful migrants would have left their mark behind in the Y chromosome.

He realised that people were interested to know their links to past generations. “With DNA you can really go deep into the past to learn where your ancestors came from,” he says.

A decade ago it was tremendously expensive to deliver a complete genome but today prices have fallen and it is feasible to think of using DNA technology to identify ancestry. About 20,000 genomes have been completed so far by labs around the world and this has opened up the possibility of direct Y chromosome comparisons between individuals and groups.

The more genomes completed, the more the resolution improves, and the better the ability to see back in time. “Up until recently we might have had a genetic signature for the northwest of Ireland collectively as being Irish. What has happened since is we can split up the Irish type. The higher resolution comes from the sequencing of the human genome.”

It all comes down to comparisons. “We look for markers and see what they are telling us,” he says. “A marker is part of the DNA that is different between people. Those differences arise with each generation.”

Most of our genome is a mix of our mother’s and father’s DNA, but the Y chromosome does not mix in a substantial way. Cavalleri likens it to the Olympic torch as individual runners carry it from city to city on the way to the games.

The same torch is passed from person to person but imagine that each person is able to leave behind a mark on the torch, a small spelling change in the DNA. “By looking at those spelling changes you get a sense of how those people have moved. After all, we are part of one big pedigree.” It is all about knowing what markers are hidden in a genome pointing towards one ancestry or another.

Almost 1,000 people have so far paid to have their DNA ancestry assessed in Scotland and the work is throwing up some surprises, Cavalleri says. For example, an estimated 1 per cent of all Scotsmen are direct descendants of the Berber and Tuareg tribesmen of the Sahara, a staggering number given the lineage is around 5,600 years old.

Scots comedian Fred MacAulay assumed he had Viking origins – via Mac-Olaf or son of Olaf. This, though, proved to be wrong, Cavalleri says. MacAulay’s DNA shows that his ancestors were not Hebridean Vikings but Irish, probably a man sold in Dublin’s ninth-century slave markets and carried off. “What we think happened is the Vikings took individuals from Ireland back to Viking bases and they had children,” he says.

“There is a fascination with this type of work,” he says, and people can now participate via the company. The male Y chromosome can be traced but it is also possible to track female lines via mitochondrial DNA only passed along by female lineages.

It costs €250 to analyse both the Y chromosome and mitochondrial DNA and €210 for either one or the other. Women don’t have a Y chromosome but often co-opt either a brother’s or a father’s DNA to show the ancestry, Cavalleri says.

The data is heavily secured and can only be used for one purpose. “The data is all stored separately on a server, it is not shared with anyone,” he says. “It is only used for ancestry. It is not used for any medical purposes. It is only used to study the history of Ireland and Scotland.”

Each person gets a web page and an account and are told the distribution of their particular maternal and paternal DNA type. The analysis will show this distribution across the world, as far back as Africa, but right up to where the type is found today, he says.

For more information see irelandsdna.com

Researching royalty: DNA fit for kings

MANY FAMILIES like to lay claim to being descended from Irish kings and today DNA can help prove this relatedness. While many family names are associated with one king or another, genetic markers can deliver the proof.

Ireland before the arrival of the Normans was dynastic, with powerful local warlords controlling territories. Their high positions in society also provided the opportunity to deliver many offspring, explains Dr Gianpiero Cavalleri, a geneticist at the Royal College of Surgeons in Ireland. It means that many of the genes passed forward into later generations had their origins in a powerful dynastic leader.

The important families are well known here, for example, the Uí Néills in Ulster begun by fifth-century warlord Niall of the Nine Hostages. Family names associated with him include O’Neill, O’Conner, O’Donnell, McLoughlin, O’Rourke and others. These surnames are associated with one particular type of Y chromosome, the male-only part of the genome.

The Eoganachta were another important dynasty in fifth-century Munster led by Conall Corc, descended from founder Eoghan-Mor. This family, with surnames such as O’Donoghue, Hayes, O’Keeffe and O’Sullivan, have a different Y chromosome type.

The Eoganachta were displaced in the 10th century by the Dalcassians, originally descended many centuries earlier from Cormac Cas, Cavalleri says. Family names here include O’Brien, Kennedy, McGrath and O’Casey, to name a few.

Then there were the kings of Laighin (Leinster) led by Dermot McMurrough who invited the Normans into Ireland. Names here include Kearney, Kinsella and McMurrough.

Few leaders had the genetic impact of the great 13th-century Mongol warrior Genghis Khan. Clearly he procreated where ever he went and today his Y chromsome is seen in 0.5 per cent of the world population, or about 16 million men. – Dick Ahlstrom

Tunnock, a three-week-old meerkat, sits in a tea cup after being weighed at Blair Drummond Safari Park in England

A researcher watches as giant panda Tao Tao climbs into a crate at the Hetaoping Research and Conservation Centre in China’s Sichuan province. Staff wear panda costumes to minimise disruption to the animals.

It’s all in the tongue: not all bees can reach nectar from the front.

Illustration: Michael Viney

ANOTHER LIFE THE TALLEST PLANTS in the tunnel just now are the thicket of broad beans (var Aquadulce) sown last autumn. Fired up by pelleted chicken manure and an early blast of sun, their whorls of bold black, white and pink flowers are swaying shoulder high, while the first pods are swelling from their shrivelled predecessors lower down the stems. I’ve never had such a promising crop – nor learned so much about one plant and its wildlife.

The beauty of a polytunnel is getting to sit down in the warm and watch things. There’s the robin, when it trusts me, and soon the odd butterfly, but when the beans began to flower I was looking out for bumblebees.

Broad beans will fertilise themselves: the night before the flowers open, the anthers inside are already shedding pollen that can reach the stigma. But a proper, cross-pollinating job between plants needs the forcible entrance of a hairy, nectar-thirsty bumblebee. There are tests to show that plants caged with bees produce longer pods with more and heavier beans than plants caged without bees.

The queen bumblebees of early spring have considerable aerial presence. I welcomed the first through the open tunnel door in early March, making – what else? – a beeline for the first clusters of bean flowers. But hey! This was no good. Instead of entering the open blossoms it perched at the back of their bells and bit through the petals to suck up the nectar within.

To regular bean-watchers, this is old news. There are bumblebees with short tongues and others with long ones. The white-tailed Bombus lucorum and the even bigger Bombus terrestris are both short-tongued. Unable to reach the nectar from the front, they are notorious nectar-robbers around the back, not only with beans but also with honeysuckle, comfrey and other flowers.

This can leave the common garden bumblebee, Bombus hortorum, unfurling its long tongue into more and more flowers, which could actually be good for bean- making. As bee visitors built up among my beans, I was cheering on the ones that chose the flowers’ front door.

Next came the great ant mystery. Veterans of this column may remember that the ants in my tunnel are not welcome. They are testy wood ants, quick to spray acid on my skin and raising big, allergic bumps that itch for days. I am trying to control them with various sinister means, but there they were, mooching around the higher reaches of my beans.

A particular insect pest of broad beans, familiar to many gardeners, is infestation by black aphids, or “blackfly”, multiplying explosively and sucking the sap of the growing shoots. In a phenomenon found worldwide, ants feed on the sugary liquid – “honeydew” – that exudes from bums of aphids, green or black. Finding this an excellent food, the ants look after the aphids, farming them like cattle, moving them around on plants and protecting them from predators. EO Wilson, world expert on ant society, sees this as an evolutionary arrangement, beneficial to both insects.

My beans, however, have no black aphids (and never had, come to that). So were the ants just hanging around, hoping for some to arrive? I fetched a magnifying glass to watch them more closely. I found them, singly and in pairs, sucking away at small black spots, the size of a match head, beneath leafy axils on the stems. Were these an advance guard of black aphids? However hard I looked, the spots didn’t move, or have legs.

An hour later I was still online in my study, tuned to Google Scholar and fascinated by something quite new to me, even though its discovery dates to 1762. Many plants, all over the world, tropical orchids and hibiscus among them, are not content to draw insects by offering nectar in their flowers. They also have features called “extrafloral nectaries”, such as the little black spots on my beans.

They are there to bring hordes of ants (“pugnacious bodyguards” in the title of one paper) to protect the plants against insect predators or parasites. It is, supposedly, another evolutionary symbiosis – plants and insects have evolved together in many mutually beneficial ways. But if black aphids arrive on the beans and the ants protect them, where is the payoff for the plants? Evolutionary biologists are still picking at a global puzzle that extends to pugnacious ants and tropical leafhoppers, caterpillars and bud-destroying wasps. Perhaps the extrafloral nectaries on broad beans (originally from north Africa) divert the ants from the aphids’ honeydew, leaving them to be reduced by predation by ladybird larvae. So much in nature is a delicate balance of odds.

There is another story about broad beans (or fava beans as much of the world calls them), involving a genetic disorder that makes them a dangerous food for some Mediterranean communities. This explains why, asking Google Scholar for “ants fava beans”, it also offered work containing “peasants”, “variants” and “descendants.”

Eye on nature

In my daughter’s garden a sparrowhawk landed very close to me with a blackbird in its talons. It moved over to the hedgerow with its prey, and I heard squealing. Such a beautiful bird, and although I got just a brief glimpse of it, I found myself thinking about it for the rest of the day.

- Finola Murphy, Bray, Co Wicklow

My neighbour’s elderly mare was standing in the field when a sudden downpour of rain and sleet struck. Two very young lambs were standing sheltering under her. When the shower ended the horse began to lick the lambs, and we were convinced that she was drying them.

- Louis and Bonnie Mullen, Riverstown, Co Louth

A robin kept coming to a holly tree outside our living-room window, hovering like a hummingbird and looking into it. Occasionally it stopped and perched on the side of the tree, moving to different levels and positions.

- Martin Crotty, Blackrock, Co Louth

It was checking it out as a nest site.

In Achill at Easter we spotted the two distinctive fins of a basking shark at the edge of the water in Keem Bay. Close by was a large seal.

GERRY MORIARTY, Northern Editor

Next summer, an A-level student from Belfast is hoping to become the youngest Irish person to reach the top of Mount Everest, but it’s not the record he is chasing, it’s the accomplishment

MATTHEW TAYLOR, a Belfast A-level student, is aiming to become the youngest Irish person to achieve the summit of Mount Everest – a dream he has entertained since his early teenage years. Sometime in the early summer of next year he hopes to be on top of the world; he will be just 19.

When, as a 13-year-old, he was first on the 850-metre Slieve Donard mountain in the Mournes in Co Down, Taylor began forming the ambition that eventually he would climb a mountain more than 10 times that height: the 8,848-metre Mount Everest, the highest peak in the world.

His first experience of hill-walking was as part of the Duke of Edinburgh scheme when, with fellow students and some teachers from the Royal Belfast Academical Institution (commonly known as Inst), he camped overnight on the Mourne Mountains. “Right from that moment I was hooked – I just found it really exciting,” he says.

When 18-year-old Taylor began telling his Inst classmates of his plans in the past year or so, some of the reaction was typical of what you would expect from teenage boys. “‘You’re going to do Everest? Aye, right!’ was what quite a number said,” he says. “But there were others too who said, ‘Go for it, Matthew.’ My teachers were also extremely supportive.”

Before he can get to the Himalayan foothills he must first raise almost £36,000 (€44,000) to be part of a 2013 Everest expedition run by the Adventure Peaks organisation, which is based in Ambleside, Cumbria. It’s obviously not the best economic time to be seeking such sponsorship, but Taylor is busily making his pitch for support to businesses, family and friends.

Taylor was also inspired by Bear Grylls, the English adventurer, writer and television presenter, who climbed Everest when he was 23. Grylls himself lived in Co Down until the age of four. A few years ago, Taylor read Grylls’s autobiography, Mud, Sweat and Tears, and was impressed not only by how Grylls made the summit of Everest, but also by how he doggedly raised the sponsorship to realise his ambition. “Bear Grylls said you may have to send out 1,000 letters to get the sponsorship, but you just have to keep going and keep going and keep going until you get there.”

Costs for the 70-day expedition, beginning in March next year, include a $10,000 (€7,562) climbing permit from the Nepalese authorities, other permits, Sherpa support, flights, hotel and other accommodation, tents, medical supplies and an expensive climbing kit of items such as crampons, ice axe, harness, down suit and gloves, face mask, sleeping bag and boots.

It’s a professionally-led “non-guided” expedition, and there are dangers involved, which Taylor and his parents – Peter, a commercial pilot, and Anne, a nurse – are well aware of. The open group of about 12 climbers will have a leader and Sherpa team accompanying them but, as stated by Adventure Peaks, they will “not be able to protect your every move and you must therefore be prepared to move between camps unsupervised”.

Taylor is also conscious that many people have died attempting Everest and many more have lost fingers, toes or limbs due to frostbite. But the spirit of adventure seems in him. “I think nowadays with the amount of safety and knowledge about the weather and so on, it is not as dangerous as it used to be.” His parents’ attitude was, “we are not going to hold you back”, he says.

In the meantime, Taylor has been gaining experience for his attempt on Everest. In February he attended a course on winter climbing in Scotland, and in August last year he climbed the highest mountain in the western Alps, the 4,810-metre Mont Blanc. He finds it awkward to put into precise words his personal sensations when he reached the summit but it is clear it is something deep and transcendent.

“At the top I had a feeling that I find extremely difficult to explain, but it was phenomenal. It was very strange. I thought it was absolutely unbelievable when I got to the top. I looked around me, and it was a clear day, there were only a couple of clouds in the sky. You could see down to Chamonix, you could see the Matterhorn – it just gave you this inner feeling that you have accomplished something quite big, after all the effort you have put in. In a strange way it is very satisfying. I haven’t really felt like that in any other way.”

For his A-levels this summer he is studying maths, physics and PE, and hopes to do an automotive engineering degree at Loughborough University in Leicestershire, and thereafter pursue a career as an officer in the British army. But first he intends to take a year out after his A-level exams to concentrate on preparing for the assault on Everest along the South Col route.

He is booked on an expedition to Muztagh Ata in China this summer. This mountain, said to be one of the “easiest” such peaks in the world to climb, is just over 7,500 metres, and will test his capabilities and endurance at high altitude.

He displays no sign of nervousness about either Muztagh Ata or Everest, just a great sense of excitement and adventure. The youngest Irish person to have climbed Everest is 26-year-old Limerickman Mark Quinn, who reached the top in May last year. American Jordan Romero is the youngest to make the summit, which he did at the age of 13.

Taylor said he would like to beat the Irish record but it’s not the main driving force behind his ambition. “It’s a factor, but I’m not doing it because I would be the youngest Irish person on Everest, but because it is a dream I have, and because of the feeling you get on top of a mountain.”

His parents are considering taking a hiking holiday in the lower regions of the Himalayas towards the end of his expedition and hope to be present when he descends from the great mountain. “They would hopefully meet me at base camp when I return. That would be nice.”

He adds: “I know of the dangers but plan to prepare for what could happen.”

There are more than 14,000 species of ants and they count for up to 15% of the weight of all terrestrial animal biomass. The ecological success of ants is only possible because they are able to adapt to and exploit their environment. Researchers at the Université Libre de Bruxelles are unlocking the secret lives of ants to understand how these complex societies work.

As kids, we all have observed ants walking in line towards some sugary treat, like a drop of soda left quite intentionally on the pavement. We were and still are fascinated about how these tiny insects are able to follow each other, find their nest, and exploit an opportune food source.

The worker ants that drink at the drop of soda are called foragers. Although they may seem numerous when gathered around the food, they only represent the tip of the iceberg. Indeed, most of the ant colony—that is, the queen(s), larvae, and domestic workers—are safe inside the nest. The majority of the workers toiling away in the nest never eat directly at the food source, but they still need energy. The ant colony thus faces a great nutritional challenge: how does it manage to feed all of its members, including the larvae and the queen, with the food harvested only by a small number of workers?

The answer is in the abdomen. Ants carry and stock the harvested food inside their midgut and can exchange food they have previously ingested. During a food exchange, or trophallaxis as it is called, a well-fed worker regurgitates part of its dinner to a hungry receiver that comes. For the queens, larvae, and domestic workers, trophallaxis is the only way to be fed.

How, then, do larvae and queens communicate how hungry they are and what food they need? A chain of demand regulates this process and, therefore, the activity of the foragers. When a larva is hungry she begs food from a worker. That worker will in turn get hungry and beg yet another worker. The begging and thus the hunger climb up a chain of workers—like a baton passed on in a relay race—until it reaches a forager. Once emptied of food and triggered by its own hunger, the forager will leave the nest and search for food. If lucky, it will find the treat we left on the terrace.

As mentioned earlier, foragers are easy to observe. One piece of fresh fruit is enough to make them come out of the nest en masse  so we can watch their behaviour. But the sharing of the harvest happens inside the multiple hidden galleries of the nest. In order to understand how ants share and actually feed, we at the Unit of Social Ecology at the Université Libre de Bruxelles constructed a simple square nest and put ants in it. We fed the ants with a sugar solution to which we added a radioactive tracer. As the radioactive tracer entered the nest along with the ingested sugar solution, a camera recorded the rays emitted by the tracer. This way we could monitor the whole sharing process inside the colony.

Ants, like all animals, live in an ever-changing environment, and the food sources available are also very uncertain. How do ants adapt to these variations? Is it better to built up stocks or is it preferable to feed all workers first?

Our research shows that the colony feeds everybody very fast—200 workers received sugar within 30 minutes—and simultaneously builds up stocks. As previously said, ants transport food inside their stomach, so the “stocks” are actually inside workers. These “stocking workers” are surrounded by other less well fed ones. Stocking workers are immobile and, because of that, we could say they are like supermarket shelves. Furthermore, only few workers act as stocks. This strategy of having a small number of heavily food-loaded workers has a great advantage: stocks can be built up and at the same time a pool of “light” workers can be efficient and active.

In fact, though we have always been told ants are hard workers, nests contain a large number of “lazy” stocking workers that spend most of their time inactive. Still, they play an important role in the colony: they are a reservoir of standby labour. And this reservoir of workers means the colony can be responsive to all kind of unexpected situations because all these “lazy” ants are ready to get to work if needed. So having lazy members might sometimes be advantageous.

The study we conducted answers some questions, but, as usual, the greater the knowledge, the greater the unknowns. We could see how ants shared the sugar, main energy source for the workers. But how do they handle proteins, which have to be given to larvae for their development? And what will happen if the food available can only feed a part of the colony? Will the ants decide to feed the workers first to keep the colony working, or feed the larvae to prime the next generation ready for better times? Ants are present in all environments. There are more than 14,000 species that have colonised all terrestrial habitats, and ants count for up to 15% of the weight of all terrestrial animal biomass. The ecological success of ants is only possible because they are able to adapt to and exploit their environment. Our research goal is to understand better the rules governing the flow of information and energy in ant society, which will gives us a better understanding of how ants have been so successful and how their society actually works. Perhaps one day the rules of ant sharing, information or energy, could be applied used to improve communication in human systems.

Aurélie Buffin
Université Libre de Bruxelles – Unit of Social Ecology
www.atomiumculture.eu