[sci.bio] question on colour change in frogs

lucyc@suite.sw.oz.au (Lucy Chubb) (05/24/91)

I have a frog (common Australian green tree frog - littoria
coerelia (sp?)) and have observed it changing colour on a
number of occasions. The colour changing could be a protective
adaptation to help the frog blend into the background (although
the colour changes seem to have nothing at all to do with the
colour of the frogs surroundings). Does anyone know what sort
of situations cause this type of frog (or other types of frog)
to change colour when it is not threatened by a predator?

		Lucy Chubb.

Softway Pty Ltd, P.O. Box 305, Strawberry Hills, NSW 2012, AUSTRALIA
Phone: +61 2 698 2322;       Fax: +61 2 699 9174;     Telex: AA27987
Email: lucyc@softway.oz.au

anderson@cshl.org (John Anderson) (05/24/91)

lucyc@suite.sw.oz.au (Lucy Chubb) writes:

>I have a frog (common Australian green tree frog - littoria
>coerelia (sp?)) and have observed it changing colour on a
>number of occasions. The colour changing could be a protective
>adaptation to help the frog blend into the background (although
>the colour changes seem to have nothing at all to do with the
>colour of the frogs surroundings). Does anyone know what sort
>of situations cause this type of frog (or other types of frog)
>to change colour when it is not threatened by a predator?

>		Lucy Chubb.

>Softway Pty Ltd, P.O. Box 305, Strawberry Hills, NSW 2012, AUSTRALIA
>Phone: +61 2 698 2322;       Fax: +61 2 699 9174;     Telex: AA27987
>Email: lucyc@softway.oz.au

How do frogs (and chameleons, octopuses, anole lizards, etc) "know" 
what color to change to to blend into the background?

-- 
John Anderson
Cold Spring Harbor Laboratory
anderson@cshl.org