> This assumes that humans and crows are physiologically identical I accept that this is partially relevant, but: Since humans choose to consume tobacco, and

> This assumes that humans and crows are physiologically identical I accept that this is partially relevant, but: Since humans choose to consume tobacco, and animals including birds generally won't (hence tobacco plants are becoming invasive), if anything we should expect humans to have a higher tolerance and crows to have a relatively lower tolerance for tobacco products. Is your point that it should be considered ethical until your questions have been exhausted? That isn't a good standard of ethics.