Is "human" a necessary category? Is it not a default-level type of information? Should not *every* character be presumed human until we are told otherwise? There is a reason why patient documents do not have a checkbox asking if we are human while veterinarian documentation requires information as to the species of their patients.
I'm having this argument with an E.T wikia, they added "Human" which is ridiculous as EVERY CHARACTER EXCEPT 1 is human. Which would mean inclusion of nearly every page on that wikia, which makes the category useless.
This is also like "Sons" and "Daughters" and "Living characters". EVERYONE is SOMEONE's son or daughter (and even Grand-), and again "living" is a condition to be expected until we are told otherwise. Somethings are just *default* information. Necessary information should be about things which are life-roles not everyone is part of. For example, unlike Sons and Daughters, not everyone is a "Parent", Father", or "Mother". Or "Siblings", "Brothers" or "Sisters", etc. And personally I'm a fan of labels which are terse and non-gender specific (ex. "Parent" plus "Male" tells us a character is a father, etc).