Change all the @ISA lines as so: 
package mammal::badger;
use vars qw(@ISA);
@ISA = qw (mammal);

--------

package mammal::badger;
BEGIN {
    @mammal::badger::ISA = qw (mammal);
}

[download]

Update: Added BEGIN{} around the @ISA assignment to fix mistake caught by PodMaster.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re: object inheritance in non ~.pm files by dragonchild
in thread object inheritance in non ~.pm files by g0n

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