 Sociality
Social insects are among the most successful of all animals. It has been
calculated that more than half of the living animal tissue on earth belongs to
social insects—termites, ants, wasps and bees. Social insects live in
colonies where collectively they share the workload and the rewards.
Ants
Ants are the most organised of the social insects. They live in a caste system
comprising workers, a queen and reproductive males. The workers in a colony are
all sterile females. The males serve only one function, which is to fertilise
the queen.
A fertilised queen will build the initial nest cells of a colony and lay her
first batch of eggs. The offspring take over all duties inside the nest and
continue to enlarge it as the colony grows. This allows the queen to
concentrate on laying eggs.
An ant colony can number less than a hundred to more than a million. They
communicate with one another by exchanging a droplet of sweet liquid—a
chemical message called an ‘ant kiss’.
Tasks such as nest building, nursing the young, attending to crops or foraging
for food are divided between the workers. Some ants even keep livestock, such
as certain caterpillars and bugs that produce substances that the ants eat.
Other ants are employed in defending the nest, and wage war against other ants.
Bees
Bee colonies can contain 60 to 80 thousand members, all of which are the
progeny of a single queen. Like other social insects, the individual is of no
importance; their lives are entirely devoted to the queen. All the worker bees
in a colony are sterile females. Males are produced at particular times, but
for breeding only.
At any one time a bee colony may have several thousand bees harvesting an area
for nectar, and they are constantly on the lookout for new areas. When a scout
bee locates a new source, it communicates its discovery to the rest of the hive
in an extraordinary way. The bees gather around a space at the hive entrance
where the scout bee performs a special dance. The type of dance informs the
other workers of the nectar type and quality, the quantity, and even the
direction and distance to the flowers.
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