De bossen van de Wielder… in de Kontaktbladen van januari en maart 2008 werden de bossen genoemd in de serie ‘Herinneringen aan een wijk’ door Frans Smeets. De bossen zijn inmiddels voor een groot deel opgeslokt door het Klaverblad Zaarderheiken, de veiling en de logistieke complexen op Groot Boller en Tradeport. Alleen een paar versnipperde bosterreinen rond het Klaverblad herinneren nog aan deze bossen van de Wielder.

Door deze bossen stroomt de Mierbeek. De beek dankt zijn naam waarschijnlijk aan de adelijke familie Van Mierlaer die ooit in Meerlo woonde. Maar een veel logischer verklaring voor de naam zijn de tientallen bosmierenhopen die al eeuwen in dit bos te vinden zijn. In nummer 17 van de herinneringen van Frans vertelde hij hoe er dode vogels op werden gelegd om de vleugels schoon te laten maken. En die mierenhopen zijn er nog steeds. Sommige vogels gaan zelfs vrijwillig op een mierenhoop liggen… om van luizen en vlooien af te komen.

Lees het hele artikel hier.

Meer informatie:

• A nest inside a wood ant nest NLLI-482
• Floriade nest nr. NLLI-186
• Floriade nest nr. NLLI-174
• Glazen dak voor mierenpad Floriade
• Floriade 2012 in Venlo

Last week the sites in the region Emmen are revisited. There are large populations of red wood ants at several sites, but at three of the sites wildfires destroyed large heathlands. The fires were caused by an arsonists.

Several nests were in or at the edge of the fire, but because only heatlands were hit the fire was not severe enough to destoy nests. One example is nest Emmerdennen-3, wich was in the fire. But after a short examination it was clear that the ants rebuild the nest. A smaller nest, about 100 meters away, was hit worse. Emmerdennen-6 is a small nest, close to a more severe fire. But the survivibg ants are moving their eggs to a new nestlocation. The fire harmed their nest, but created a much more suitable place three meters away. More severe fire was at the Kampervenen-17 nest. One nest was in the middle of it, but also here there are surviving ants building a new nest. The largest fire was on the Molenveld near Exloo. One nest, MD-8, on the edge is recovered from the fire.

It seems that wildfires on heathlands are not severe enough to destroy complete wood ant populations. The nests seen last week are all recovered, or the ants are building a new nests. These nests go deep underground, probably deep enough to protect the ants against heat and smoke. But what is very interesting is that these ants did also find a way to keep oxigen inside the nest. Did they close the many entrances to the nest before the fire arrived? Two interesing observations were also that wood ants use carbonized materials to rebuild the nest, even while there is fresh matrial available. The other observation is that wildfires also create new opportunities for ants, like Emmerdennen 7. Even when un burned sites are available, the ants chose a brand new location to build their new home.

Beside these wildfire observations there are 145 new photo’s and 185 nest observations added to the database. About 70 new nests were discovered. The updates are available at: Bargeres, Emmerdennen, Emmerschans, Hunzebos, Kampenvenen, Molenveld, Noordbargerbosch, Schuttersbosje and Valtherbos

Another amazing ant-fact: the largest super colony spreads over 16 countries on 6 continents.

Ants build colonies. Ants that live in the same colony recognize each other. You can put one ant from the colony easily with one other from the same colony and they greet each other. But do this experiment with ants from the same species but different colonies, they will harm each other. The biggest ant colony ever found was discovered in Europe in 2002 from Argentine ants (Linepithema humile) . The Catalonian super-colony follows the coastline from Italy to France to Spain and Portugal.  The length of this colony is 5760 kilometers. They discovered it by putting ants from Portugal in the same box as Italian ants. And they didn’t harm each other. The researchers could draw only one conclusion: these ants must be from the same colony. Now researchers discovered that this super colony is just a mart from an even larger mega colony. It stretches out over almost all continents and many countries. They discovered it when ants from Europe where not hostile to ants from the US and Japan.

The researchers believe, based on this experiment, that argentine ants built the largest super colony ever discovered. It’s enormous scale concurs the the size of the global network of human. So the idea that ants are taking over the world seems to be very realistic. But are they? Ants living in the same colony have the same smell. Does an ant smell different, than both ants avoid each other  or get harmful. The ants in the experiment rubbed antennae, that means that they share the same chemical profile and are part of the same colony. Who fears an ant controlled world can back to sleep: the ants did not create this enormous colony themselves. It was created by people, transporting ants while traveling or shipping goods.

This is a great discovery, but it puts the word ’super colony’ in a totally new perspective. Comparing it with human it is clear that there are big differences. For example the human super colony that is as large as the world. Cultural differences, religion and law cause war between countries, even cities streets. But countries can also unite to larger networks, like the US and the European Union. Only the network of roads and tracks made by human is a global phenomenon. But even this infrastructure network is cut apart by wars and laws. (Take the old Berlin, where one urban transportation system was cut in two after world war II by the Iron Curtain…). To compare the Argentine ant colony with the human colony we should look out for connecting roads between nests, food sources and boundaries, like the wood ants do. These ants build networks of nests and roads connecting single colonies to networks with the size of a small town.

A network of connected nests fits the idea of an super colony better than a collection of disconnected nests of ants with the same smell. Maybe the argentine ants just cant’s smell? The word colony and super colony must be redefined. Researchers can not call the Argentine colony a super-colony, only based on a chemical profile. They should also look at the connections between nests, the natural way of distribution and the way how these ants cooperate with other species (like wood ants do).

• NU.nl
• BBC
• Wikipedia

You’ll find an updated map and more information here.

These Amazon ants are rare. The scientists wonder how these ants could evolve. Social insects have different ways to reproduce, but this asexual way is very unusual. The key could be found in another special behavior: cultivating huge amounts of fungus crops. they produce much more of it than other ant species. Their rare reproducing ability could be related to the reproduction of the fungus, witch is also asexual.

The reproduction of Mycocepurus smithii seems to be successful. But one large question comes to the biologists mind: how is it possible that these ants with all the same DNA can survive? The most successful reproduction starts with creating more resistant strings of DNA. These ants do not develop at all, but are inbreeding constantly. This could cause diseases and weaknesses during time making the ants not last long.

It seems this species did survive for ages anyway which makes them some kind of ’super ants’. Or more speculative; they are mutant ants, the result of some environmental disaster. Who knows…

The reason that these ants spread so fast is that they travel with compost. Gardeners bring soil and plants from one place to another. And bring the ants with them. Entomologist fear the worst for the indigenous species, like Lasius niger. The Lasius neglectus nests contain 10 to 100 times the number of ants as L. niger.

Lasius neglectus ants live in gardens close to human. Just like Formica rufa they create networks of several nest, connected by roads. This makes it extremely difficult to control this pest. They make also roads into houses and kitchens. These networks of nests are also called super colonies. In a L. neglectur super colony can live ten thousands of queens.

A supercolony can grow to 14 hectares big and there live probably more than 100 million ants. They mate under ground and have no mating flight.

Link: distribution

Link: Evolution

Black garden ants are also known as black ants, house ants or brouwn ants. The scientific name is Lasius niger. They build tunnels and mounds in the garden. From there they explore the entire area. L. niger does like urban places. Where people live, these ants do too. On the internet you can find hundreds of ways to get rid of them. We have them in our house too, some times. But only a few. How is that possible, with ant colonies under the pavement, in the garden and even under the house…

One reason is probably our back yard itself. The garden is not entirely covered with stone and concrete. We left a lot of space for plants to grow. We do not use all kind of insecticides to protect the plants against insects. And we also do not clean the garden properly. This means that other insects and animals can get a lot of food. And this means that the ants do also have a lot of supplies. Ants do not need to explore our house.

The second reason we do not have a lot of ants is the pest control. Each time we see an ant in our house we kill it instantly. The ant cannot make a trail for the other ants. We also remove the trails with vinegar. All ants coming in lose the way…

But (here comes the but) this is only something we asume. Anna studied the colored ants and measured the time ants needed to perform their tasks. Then she compared the time made by specialized ants with the time made by not-specialized ones. The result: there was no difference. Specialized ants are not faster or better in the job at all. The big question now is this: if specialization makes no difference, then why do ants get specialized tasks?

Maybe the ants studied decent of ancient ants that did realy specialize. Army ants for example are built for their task. Or maybe the Temnothorax albipennisis is evolving to a species like that?

Reference: Specialization Does Not Predict Individual Efficiency in an Ant

This week in the news: Ants have a simple solution to traffic congestion at newscientist.com. This was discovered by collective intelligence expert Dirk Helbing from the Dresden University of Technology in Germany. He and his team created an ant colony and a food source, connected by two adjustable roads.  The idea was to test the ants response to changes in the width of the two connections. They started with two similar and wide connections, and the ants chose only one of them. Following the chemical trails ants use to mark their tracks. The researchers then started to narrow one of the roads. And at some point the ants started to use the second route too, without the chemical trails. It seems that the more ants bump to each other with their heads, the more the need to create parallel roads.  Ants who bumped to much can tell their family members with another chemical message that they should take another way. This is an easy and very efficient way to prevent traffic jam. Find the original report here.

This method the ants use could explain two observations in wood ant super colonies. One is that there are sometimes two-lane ant roads between two nests. The second is that when there are two or more very large nests close together, that some ant roads follow a trail around one of the nests, like a ring way. In both observations it is clear that the ants must use some way to find a faster and more efficient way than the shortest. The answer how the ants do that is now discovered.

An example of two or three lane roads is Super colony Ravensheide-1 on this map.