I have read on a post about a "thumbprint" on the back of a budgies head meaning he is a pied. Is this where the lines are not straight and have different designs?
The thumbprint you mention is called "pied patch".
I can show you a few examples with my flock:
Here is Leonel, my dominant pied budgie, notice the white patch located on the back of the head where the barring of his zebra pattern should be.
This is Peppy, a recessive pied budgie. The extent of her pied patch covers more feathers and her barring on the back of the head is practically non-existent. DSCF3173 by aluz391, on Flickr
The same thing goes for my recessive pied girl, Goldilocks (budgie on the right) DSCF3399 by aluz391, on Flickr
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RIP sweet Tito (Summer 2008 - January 17th 2013).
You are missed and never will be forgotten.
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thumbprint???
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