[username90]

Animals works well as tools, but they don't work independently. In all of the situations you described there are humans present to direct the work and life of the animal, something you don't need with humans. I'm not sure why we can't get them to work independently, I guess they lack the attention span or the ability to associate the work with the rewards.

[codyb]

I suppose the one sort of exception to this would be barn cats who sort of self domesticated themselves and became valued members of households by keeping rodents at bay.

Cats also seem pretty intelligent to me.

[ianai]

You’re going to have a hard time finding a job without a supervisor or boss that isn’t CEO/entrepreneur/similar.

Nobody should expect another species to share our concept of a capitalistic market, for that matter.