Board Thread:General Discussion/@comment-70.27.62.150-20131011194647/@comment-226878-20140429035927

For hundreds of years, much of humanity believed that animals didn't have souls.

As for Grimm attacking humans, I believe we have yet to see Grimm attack anyone who isn't equipped with dust-modified weaponry. The world history states that man developed dust as a weapon to battle Grimm, so maybe Grimm have a natural aversion to it and see anyone carrying dust to be an enemy.

Large bears, large cats, alligators, crocodiles, many species of snake, spiders, scorpions, and some species of fish and sea-faring mammals are not reprogrammable, their baser predatory and territorial instincts making them combative toward humans who try to domesticate them. Usually, these baser instincts are activated by pheromones humans produce when they are unable to suppress their fear. The predatory/territorial animals mistakes this as a precursor to aggressive action and strikes first.