User blog comment:JeielYozama/4 Little Ladies.../@comment-28144855-20170106235907/@comment-28144855-20170119200728

I'd say every living thing have some value in the ecosystem. It is us Humans who if doesn't see any value or mean of exploit in an animal in a proffitable or beneficial for us way it is worthless.

There is a joke in my place that goes:

Who is the king of the animals?

Most answer: Lion.

Then the counter answer is: I don't know, but untill I taste the lion it's definitely the pig!

I deem useless whatever I can't eat. You'd be surprised how good some things taste, It's mostly psyche that tells you 'I can't eat that' or 'it's disgusting because it's this or that'. Mice are useless by that standard, same as many many species.