Ants are everywhere, but poorly recognised and appreciated unlike other larger organisms like butterflies and birds. They play a dominant role in tropical ecosystems and have achieved unprecedented ecological success. For example, in the Brazilian tropical forests, ants have been estimated to have a biomass four times that of all vertebrates put together.
Ants are social insects, ie they live in groups. They belong to Order Hymenoptera and Family Formicidae. The Family Formicidae is further sub divided into 11 subfamilies of which ants from only 6 sub families are known to occur in India. Every day new discoveries of ants are being reported the world over and the present number of ants known worldwide is 11,006 species. Of the nearly 700 species of ants known in India, about hundred of them have been recorded from Bangalore alone.
Important features of ants :
Ants have three pairs of legs.
They live in groups.
Co-operative care of the brood.
The ability to produce winged (reproductives) and wingless females workers.
Morphology
The body an ant is divided into four segments; the head, alitrunk, petiole and gaster or abdomen.
The head contains the eyes, mouthparts and the antennae. The antenna has a long first joint (the scape) and a larger number of smaller joints (the funinculus).
The alitrunk is the portion between the head and the petiole. It is formed by a fusion of the thorax and first abdominal segment and has three distinct parts, the pronotum, mesonotum and propodeum or metanotum.
The petiole or the waist of an ant is found between the alitrunk and abdomen. All ants have it and is a characteristic feature for identification. The petiole is a specialisation of the second segment of the abdomen. In some ants, the petiole is followed by a post petiole. Sometimes the petiole has spines of different shapes for defence.
Size and colour
Ants vary in sizes. They can be as small as 1 mm and as large as an inch. In majority of the ant species, the queen is bigger in size when compared to the workers. Drastic are their colour variations, from black to brilliant red, brown to olive green and from shades of grey to orange. Some ants are coloured completely orange or red or show shades of brown, while some are completely black, others have a combination of colours such as body being orange red and abdomen black. The hairs on its body (also called pubescence) can mask the true colour of the body and make it look different. For example, one of the commonly seen ant in Karnataka, the Golden Back Ant, has shiny golden hairs on its abdomen making the entire abdomen appear golden coloured while in reality the colour of the abdomen is black. In some of the ants the grey hairs on its body can make the ant appear grey in colour but the body may be black in colour.
The ant family
An ant family consists of the queen, workers and male ants. In most ants the queens are usually bigger in size with a huge abdomen compared to the workers. Unlike the bees, she does not retain her wings after setting up her colony. Her main task is to lay eggs while her daughters (the worker ants) work for the colony by bringing food and water, feeding the young ones, cleaning the nest and defending the colony from enemies. Worker ants are the ants that we usually see out in the open. The workers whose job is to defend the colony are called soldiers. They are bigger in size compared to the workers and have oversized heads and jaws and sometimes use these jaws to crack open the hard seeds to feed on. Male ants can be seen occasionally, they mate virgin queens from other colonies and die shortly afterwards.
No worker ant lives alone. She needs the company of her sisters and her mother. They live in groups consisting of a few hundreds to more than a million sister ants in a single nest. By living in groups they ensure that young ants are produced and that they live.
Nests of ants
Ants nests mainly under the soil and on trees, but in houses they nest in the cracks of walls and floor. The inner portion of a nest is designed in such a way as to provide proper humidity and temperature for the growing young ants. Nests are designed with several chambers for the queen, workers, the young ones and also for dumping wastes similar to our garbage bins. One type of ant collects fallen bird feathers and decorates its nest entrance with it. It uses the feathers to capture the morning dewdrops. The feathers acts as a water collector. She thus saves time and effort for fetching water to the colony.
Have you seen an ant nest made of leaves hanging on trees? These nests belong to the weaver ants. These ants are orange in colour, about 1 cm in length and noted for their bites. Watching these ants build a nest is absorbing. They build their oval shaped nests on trees using leaves of the tree. The leaves are glued together by using silk from their larvae. Workers bend the leaves by applying weight on the leaves or sometimes by pulling them with their teeth like structure called mandibles. Sometimes, these ants also form chains by holding one another and stretch across gaps that are too wide for a single ant. This reveals the extent of cooperation that occurs in ant societies, but absent among humans.
Some ants also help in reducing pests on trees by feeding on them. Weaver ants were used as early as 304 AD in China for controlling pests. These ants and their nests were gathered and sold in markets. The nests were placed in lemon and orange orchards to kill other insects. This is also practiced in some parts of Kerala. Weaver ants are also eaten by tribals in Bihar and Orissa. Dried ants are used in making curry.
Tour leader
Sunil Kumar M has been working on ant diversity from 1996 onwards in Bangalore and several forest regions of Western Ghats in India. His specialisation has been in the field of Environmental Science at the Masters level, with the research emphasis being on ant taxonomy, study of biodiversity and on ant behavioural aspects. During 1996 and 1997, he worked at the Centre for Ecological Sciences, Indian Institute of Science, Bangalore on ant diversity. Later, from 1997 to 2000 he focused his work on the large issues of biodiversity and conservation with emphasis on the role of environment education at the Centre for Environment Education (CEE), Bangalore. CEE is a National Institute recognised by the government as one of the Centres of Excellence in India. The work was funded by various agencies including the World Bank, Norwegian Agency for Development and Co-operation, Global Environment Facility, McArthur Foundation, and the Karnataka Forest Department. He has been a co-investigator for a biodiversity assessment project in Savandurga Reserve Forest (1998 to 2000) and also was a co-investigator for a project on biodiversity assessment in Bannerghatta National Park. Besides authoring several popular articles on ants, he has also authored a book on water quality monitoring and currently writing a book on the Biodiversity of India. On the personal front, from 1996 onwards, he has been trying to popularise ant watching by conducting audio-visual presentations, trails and camps for students and naturalists.
The Sloth Bear Foundation is a non-profit, self-reliant and independent organization registered as a trust. Participation in tours and expeditions contributes the needed money to fund the SBF conservation and rehabilitation projects.
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