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Author Topic: How Does A Cuckoo Know It Is A Cuckoo ? and other questions too !  (Read 2440 times)

Offline neilep

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OK ewe got the Reed Warbler yes ?..a really cute tiny bird smaller than a Sparrow !

...Ewe then got a Cuckoo !...much larger but very clever/sneaky......

The Cuckoo egg looks similar to the Reed Warblers egg in appearance and size !...the size thing is very clever/cunning because the Cuckoo is so much larger and thus a comparably sized bird would lay much larger eggs !

OK..so the Reed Warbler is fooled by the appearance and size of the Cuckoo egg. The Cuckoo lays it's egg to time so that it hatches before the Reed Warblers eggs hatch......Thus, when the baby Cuckoo hatches it pushes the Reed Warblers eggs out of the nest.

Here's more klevur stuff !..the cheating continues.......the baby Cuckoo mimics the sound of the baby Reed Warbler so much more so..... that the Reed Warblers feed the baby cuckoo at a highly charged rate.

So,ewe have an egg that looks similar and a baby Cuckoo that somehow has an innate knowledge to mimic the call of the baby reed warbler ..OK ?...with me on this ?


OK...take a look at this picture.



The baby cuckoo is a giant compare to it's foster parents who still think it's their baby !!

Three questions : How Does The Cuckoo Know It Is A Cuckoo ?

and after going to so much trouble to replicate an egg that looks similar in size and appearance and then the mimicry of the baby Reed Warbler...How Come The Reed Warblers Are Not Phased By The Obvious Appearance Of The Baby Cuckoo ?


How Does The Baby Cuckoo Learn To Mimic The Reed Warbler Cry ?


whajafink ?



Ta
« Last Edit: 05/04/2011 14:06:15 by neilep »


 

Offline RD

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The matching egg and matching cry came about through natural selection : they are innate, not learned, characteristics.

If the cuckoo chick has kicked the other eggs out of the nest before they hatched it can’t have learned what the warbler chicks sound like, so it’s warbler-like cry must be innate.

The cuckoo’s parasitical behaviour will also be innate, it doesn’t have to learn how to be a cuckoo,
If female it may learn (imprint) the “host” species (whose eggs it matches).
 

Offline neilep

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Thanks RD....very helpful and greatly appreciated....

.............but what about the fact that the Reed Warblers readily accept their mammoth non-Reed Warbler looking chick ?
 

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