Indian koel :-
Scientific name:- eudynamys scolopacea
General features:-
Female sometimes known as spotted koel.male with red eyes and black body.female is brown coloured or reddish brown in colour with white dots or lines covering the body.
Malayalam names:- (കുയില്,കാക്കകുയില്,കോകിലം)
male female
There are many varieties of koel in Kerala.the common sounds of ‘koovu-koovu,are of the common koel.there are many mystical stories about koels in Kerala,one of them being that they bring “red-eye” diseases for children.
Most of the members of the koel family have a characteristic behavior for them.They don’t build nests themselves but utilizes the space and care of other bird,mothers, by laying eggs in their nests and letting them raise their young ones.
The Indian koel usually lays eggs in the crow,s nests.when the time for nesting comes a female koel searches for a suitable nest for laying.they lay their eggs in the crows nest when they go for foraging or when a time comes when the crow pair is not in the nests vicinity or by outsmarting them by tricks.they lay their eggs quickly among the crows eggs.
By way of evolution,the eggs of both crows and koels have been designed to look alike and so the poor crow pair usually never notices one or more of the koels eggs among their own and start incubating them all.
Immediately after the koel egg hatches some extraordinary and terrible(or so) things happen in the crows nest.before even their eyes open the koel chick vibrates or spasms out vigorously and pushes out the other crow eggs which have not still hatched and ensures that the fod the crow pair collects will be available for it.this is a phenomenon which have been perfected by the koel chicks to ensure the survival of its kind.this behavior is said to be an involuntary natural response to its kind perfected over the years(evolutionary years).and more over the koel chick is a;almost a perfect look-alike of a crow chick as long as it is dependent on the crow pair for survival,even the females striped color or appearance appears after the nest-dependent phase of its life is complete.
These are examples of natural adaptation of species occurring around us perfected by evolutionary natural selection.
Even today the truth behind the koel-crow relationship is only vaguely known to scientists.there are many views among them that the bird chick(koel) doesn’t actually kill the other eggs by pushing it down and that the koel will care for their young ones once they are hatched.
Not only does the koel give its housekeeping duties to other birds but also is said to attack other bird nests for eggs.
How did a species get to be so selfish and so adapted to its methods??
The answer is not simple but to explain briefly,every organism in this earth have acquired certain qualities in time for ensuring the better sustenance of its kind,for example our hands are the result of evolution from front legs of other former species.the same process culminated in the case of koels with the result of their cunningness and dependence of their nesting life for other birds.
In earlier times when first the species of koel emerged the could have been normal birds like many others,racing their young ones themselves,but in time a smarter bird came into being or circumstances of nature led to the development of the species to that of a nest borrower and this single change could be the reason of the behavior in it developing as a new species.The proof that this behavior led to the development of a separate species can be seen even today in the “
southern caucal”,which is a neighbor species of the koel who have developed the normal behavior of nesting themselves.
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