If you want to copy nested hashes, consider Storable dclone. For example, if %hash2 looks like this: 
%hash2 = ( mammal => { dog => 'a', cat => 'a' }, bird => {...}, ... )

[download]
{ %hash2 } will only copy the data 1 level deep. edit: removed link to perl cookbook

In reply to Re: Initial Hash of Hash by value by believer
in thread Initial Hash of Hash by value by Anonymous Monk

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