Sure, but it helps a lot. A lot of the chemicals in question attack aspects of physiology that many animals have in common, especially if you're observing other mammals. You'd not be guaranteed safety, but you'd avoid most of the worst ones I'd reckon.

Yes. Brian from Family Guy had mushrooms one episode. Bojack Horseman did drugs to write his autobiography. Pretty sure Snoopy smokes weed, and Scooby Due is definitely second-hand high from Shaggy all the time

Supposedly reindeer will eat psychedelic mushrooms. Shamans would collect their urine and drink it to trip, i mean vision quest. The theory is the animal filters out the toxins but the psilocybin is just expelled.