You
must have heard the shrilling sound of certain insects at night in the rainy
season that passed by. Ever wondered where they have gone these days? Have they
died or gone somewhere?
Many
insects like crickets and grasshoppers are heard during the rainy days, i.e.,
late summer and early autumn. They make sounds and it is hard to locate the
source of sound. It can irritate a person and they leave you with no other
option than to tolerate their song.
During
winter the grasshoppers and crickets slow down their activities and hide
themselves in a suitable place such as cracks and crevices in the rocks etc.
Insects
do not have the ability to regulate their temperature by generating body heat
so they are ectothermic. They take on the temperature of their surroundings. You
avoid going out of your home to play when it is very cold outside. Similarly
these singing insects too find a quite place for themselves and stop activities
to conserve heat.
In
many cold countries, where winters are longer and freezing, adults and nymphs die.
But how do they appear all of a sudden when the temperature rises? Yes, because
when the winter ends, their eggs hatch into new crickets and grasshoppers. And
they survive the winter season as eggs.
How
will you know that the song whose source you are unable to identify is of a
grasshopper hopping around outside or of a cricket’s? Well, crickets sing
during the night and the grasshopper during the day. In movies to portray a
scene of night, a background shrilling sound of cricket, called jhingur in Hindi is played.
Every
cricket and grasshopper is not a singing insect. Only males sing to call
females for mating or warding off other males. So when they sense the correct
time for mating they start singing.
Now
the big question is how do the singing insects sing? Do they have vocal cords
in their necks as we do? It is strange but the sound which they produce is not
generated by some vocal cords. They sing by rubbing together their two parts of
the body.
Crickets
rub together roughened parts of their wings. Grasshoppers rub their legs
against their forewings. The legs of a grasshopper have a row of ‘tiny-pegs’ on
them which they rub against the hard vein on their forewings.
What
is even more strange is that these singing insects have ears on their first
pairs of legs or on either side of their abdomen!
Singing
of crickets is considered a sign of good luck in China. They are popular pets
there and kept in cages. In some European countries particularly in Iberian
Peninsula, Mexico, South East Asia people use ‘cricket fighting’ as a gambling
sport.
What
do the singing insects eat, do you know? Like different people eat different
things, some prefer to eat non-vegetarian food and some eat vegetarian food.
Similarly different singing insects eat different things. Grasshoppers are
vegetarian but crickets eat small insects, plants and moulds.
