Our school days
were lost without our understanding many things – remember this English poem of
William Wordsworth (1770 – 1850), an English romantic poet whose magnum opus is
considered to be ‘the Prelude’ : this was ‘butterfly’
I'VE watched you now a full half-hour;
Self-poised upon that yellow flower
.. .. .. ..
I know not if you sleep or feed.
How motionless!--not frozen seas
The opening
lines reveals his apparent entrancement.
It perhaps was no poem on a simple butterfly, but
more of what it could represent ! It's fragile, delicate, short lifespan and every moment could be
it's last, with all the "predators" out there. Though we take solace planning longer things,
our life too is fragile…
Not as attractive is the one that we see generally when it
is cloudy and about to rain – a dragonfly,
an insect belonging to the order
Odonata, having hindwing broader than front wing. Adult dragonflies are
characterized by large multifaceted eyes, two pairs of strong transparent wings,
sometimes with coloured patches and an elongated body. Dragonflies are agile
fliers, while damselflies have a weaker, fluttery flight. Have seen blue, green and black dragonflies –
not red ones.
Dragonflies are predators, both in their aquatic larval stage, when they are known as nymphs or naiads, and as adults. Several years of their lives are spent as nymphs living in fresh water; the adults may be on the wing for just a few days or weeks. Found nearer water bodies, they have a uniquely complex mode of reproduction involving indirect insemination, delayed fertilization, and sperm competition. Adult dragonflies eat other insects and can consume hundreds of mosquitoes in one day! They are valued predators, since they help control populations of harmful insects. Dragonflies are usually found around lakes, ponds, streams and wetlands because their larvae, known as "nymphs", are aquatic. Adult dragonflies do not bite or sting humans, though nymphs are capable of delivering a painful but harmless bite.
Loss of wetland habitat threatens dragonfly populations
around the world. Dragonflies are represented in human culture on artifacts such
as pottery and paintings. An article in NewYork times stated that one research team has determined that the nervous
system of a dragonfly displays an almost human capacity for selective
attention, able to focus on a single prey as it flies amid a cloud of similarly
fluttering insects, just as a guest at a party can attend to a friend's words
while ignoring the background chatter. Other researchers have identified a kind
of master circuit of 16 neurons that connect the dragonfly's brain to its
flight motor centre in the thorax. With the aid of that neuronal package, a
dragonfly can track a moving target, calculate a trajectory to intercept that
target and subtly adjust its path as needed ... As a rule, the hunted remains
clueless until it's all over. That is
more akin to a ‘stealth fighter craft’.
Dragonflies have two sets of wings with muscles in the
thorax that can work each wing independently. This allows them to change the
angle of each wing and practice superior agility in the air. Dragonflies can
fly in any direction, including sideways and backward, and can hover in a
single spot for a minute or more. This amazing ability is one factor in their
success as aerial ambush predators — they can move in on unsuspecting prey from
any direction. Not only are they agile, but they're fast, with some species
reaching a top speed of 18 miles per hour. Dragonflies lay their eggs in water,
and when the larvae hatch, they live underwater for up to two years. Actually,
depending on the altitude and latitude, some species may stay in the larval
state for up to six years !
On a trip to Thirunarayanapuram(Melukote) and then to the
avathara sthalam of Sri Thirumalai Ananthalwar, Hale Kiranguru near Sri
Rangapatna, nearer the small beautiful pond, saw some ‘red dragonflies’ – which
is the subject matter of the post.
Understand that the red-veined darter or nomad is a dragonfly of the genus Sympetrum. It is a
common species in southern Europeand from the 1990s. Males have a red abdomen, wings
have red veins. and the wing bases of the hind-wings are
yellow. The pterostigma are pale - they
reportedly could be found in Europe, regions of the Middle East and some
regions of southwestern Asia like Sri-Lanka, India, and Mongolia.
May not be most exotic, yet this one was quite attractive
!
With regards – S. Sampathkumar
8th Oct 2o16.
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