Saturday 26 November 2011

Panchasayar, Kolkata, West Bengal, India

The Private Life Of Ants

How can this be?! Ants are so tiny, and we are so big! But scientists estimate there are at least 1.5 million ants on the planet for every human being. Over 12,000 species of ants are known to exist, on every continent except Antarctica. Most live in tropical regions. A single acre of Amazon rainforest may house 3.5 million ants. Ants have the largest brain in proportion to its size. They are known to be the smartest species of insects with about 250,000 brain cells.


Ants evolved some 130 million years ago during the early Cretaceous period. Most fossil evidence of insects is found in lumps of ancient amber, or fossilized plant resin. The oldest known ant fossil, a primitive and now extinct ant species named Sphercomyrma freyi, was found in Cliffwood Beach, NJ. Though that fossil only dates back 92 million years, another fossil ant that proved nearly as old has a clear lineage to ants of present day. This suggests a much longer evolutionary line than previously thought, leading scientists to estimate the appearance of ants on Earth as somewhere around 130 million years ago.


Although ants have two eye but in those two there are many small eyes. They are called compound eyes. The abdomen of the ant contains two stomachs. One stomach holds the food for itself and second stomach is for food to be shared with other ants. Like all insects, the outside of their body is covered with a hard armour this is called the exoskeleton.


The job of the queen is to lay eggs which the worker ants look after. Worker ants are sterile, they look for food, look after the young, and defend the nest from unwanted visitors. Ants are clean and tidy insects. Some worker ants are given the job of taking the rubbish from the nest and putting it outside in a special rubbish dump! Each colony of ants has its own smell. In this way, intruders can be recognized immediately. Many ants such as the common Red species have a sting which they use to defend their nest.


The common Black Ants and Wood Ants have no sting, but they can squirt a spray of formic acid. Some birds put ants in their feathers because the ants squirt formic acid which gets rid of the parasites. The Slave-Maker Ant (Polyergus Rufescens) raids the nests of other ants and steals their pupae. When these new ants hatch,they work as slaves within the colony. The worker ants keep the eggs and larvae in different groups according to ages.


At night the worker ants move the eggs and larvae deep into the nest to protect them from the cold. During the daytime, the worker ants move the eggs and larvae of the colony to the top of the nest so that they can be warmer. If a worker ant has found a good source for food, it leaves a trail of scent so that the other ants in the colony can find the food. Army Ants are nomadic and they are always moving. They carry their larvae and their eggs with them in a long column.


The Army Ant (Ecitron Burchelli) of South America, can have as many as 700,000 members in its colony. The Leaf Cutter Ants are farmers. They cut out pieces of leaves which they take back to their nests. They chew them into a pulp and a special fungus grows it. Ants cannot digest leaves because they cannot digest cellulose. Many people think ants are a pest but I like them. To stop them coming into the kitchen put some sugar outside. They they have so much to eat that they are not interested in coming into the kitchen.