In most genome sequencing applications, at a given locus there are at most two variants, present in equal proportions (ie the two alleles in a diploid individual). In situations like these, the high error rates of next generation sequencing technology are not a large problem, as any errors are likely to be present at much lower frequency than reads from the true variants, so are easy to filter out. There are some situations, however, where variants are present at low frequency in the sample. Examples would include sequencing a tumor, which is a collection of cells all of whose genomes may have diverged from the founder cell; sequencing mitochondrial genomes, as each cell contains many mitochondria, not all of which will have the same genome; or sequencing pooled genomes from a population of individuals in order to detect rare variants. In each of these cases, it is possible that true sequence variants will be present at a frequency similar to the frequency of sequencing error. In an article just published in Genome Biology, Mingkun Li and Mark Stoneking present a method that statistically analyzes detected variants in order to differentiate true variants from sequencing error. As well as being a very useful method, this publication is of note because the work described won the poster prize at last year’s Beyond the Genome conference, organized by Genome Biology and Genome Medicine in Washington DC last year. We hope that this year’s conference, in Boston in September, will result in similarly high quality submissions.

World Migratory Bird Day hopes to increase awareness about the threats birds are facing across the globe. With migratory birds relying on multiple habitats, this makes them even more vulnerable to change, so understanding migration routes is vital in learning where to focus conservation efforts. Test your knowledge of bird migration with our quiz.

Facts About Black Garden Ants

black garden ants

Black garden ants are representatives of one of the species belonging to the ant family. They are found in Europe, in parts of Asia and in North America. Black garden ants form well-organized colonies in which each individual performs its function: some are responsible for reproduction, others – for order, and others are working.

Latin name: Lasius niger
Family: Formicidae


Like most of their relatives, the black garden ant ration is rich and diverse. Working ants who are looking for food have plenty to choose from. Ants usually behave like predators that catch and eat insects of other species. However, ants also like fruit and honey. Their favourite dish is honeydew. That is why working ants are looking for plants containing aphids. They “milk” the aphids — touch their bodies and rub them with their antennas to make the insect pick out a drop of sweet dew. Often the workers carry the aphids into an anthill, where they keep them in special chambers and provide them with food: so they solve the problem of finding their favourite food – it is always near. In the autumn, black garden ants look for eggs by aphids and bring them to the anthill, making supplies. In spring, ants take eggs out of aphids and attach them to plants.


Black garden ants build anthills in different places – under small lumps of earth, roots and trunks of old fallen trees, in rotten stumps, under flat stones or in the walls of buildings. The anthill leads to a narrow entrance, from which corridors lead into several main chambers, which are also interconnected by corridors. Each camera has its own purpose.

Black garden ants form large, well-organized communities. Each individual has a specific function. The inhabitants of the colony are divided into 3 castes — the queen (breeding female, which lays eggs) breeding winged male) and working ants (infertile females).

Some workers take care of eggs and larvae. Others build or expand an anthill, maintain order in it. The third group of workers goes in search of food. There are workers who care for the queen and guard the anthill. The queen spends all her life in a separate chamber, her function is the continuous laying of eggs. The first generation of a new colony is developing very quickly, the ants immediately start building an anthill, taking care of the queen and the next generation of larvae.


Once a year, usually in June or July, the winged young queens and males leave the anthill and set off for a mating flight, their packs are sometimes so numerous that they can even interfere with traffic. Ants mate in flight. During the only mating flight in her life, the queen receives so much sperm from the male that she has enough for her whole life.

With the end of the mating winged males die, and the queen descends to the ground and digs a small hole, which will become the basis for the future of the anthill. The female lays the first eggs only after a few months. Throughout this time, she lives at the expense of those energy reserves that are accumulated in her body. The queen usually uses wing musculature, which she no longer needs. After the end of the month, the female lays fertilized and unfertilized eggs. Working females will hatch from fertilized, and males from unfertilized. In the initial period, the queen feeds the larvae with her saliva. After the larvae turn into pupae, it will take a little more time for the working ants to come out of the cocoons.


  • Antennas: these are the most important sense organs of touch, taste, hearing, and smell. They look like thin strings;
  • Mouth apparatus: consists of a pair of tentacles that serve to collect food and carry cocoons;
  • Eyes: compound eyes consist of many small lenses, each of which registers only a part of the object that is observed;
  • Chest: The middle part of the body, from which three pairs of limbs grow;
  • Legs: consist of 9 segments that are connected by movable joints. At the ends of the legs, there are two claws with hooks on which the insect rests while walking. With their help, the ant digs the ground and climbs the walls.