Of course animals have some degree of autonomy compared to, say, a leaf blowing in the wind. Life is the first anomaly, personhood the second. Animal behaviour is just more instinctive and reactionary than personal behaviour because there's less of a straightforward biological explanation of human actions. That's because when you have the tangled knot of personhood (based on the added layers of culture and brain processing we have), you have to add psychology, sociology, and references to culture to account for the complex symbols we use that further detach us from nature.

My philosophy is naturalistic, so the dualism I draw between people and animals, or between artificiality and the wilderness isn't Cartesian or absolute. There are degrees of autonomy, beginning even with the simplest membranes that protect single-celled organisms from the vicissitudes of the environment.

I'm not clear what your quibble is about Buddhism. Something to do with whether nirvana is an end goal or a byproduct? My criticisms of Buddhism aren't that detailed.