It has been said of all the senses, scent, a sense of smell is amongst the last to go, possibly because it's amongst the first to make bindings in the brain, with a remarkably direct path. Old people with aphasia and dementia can be brought into quite alert states with smells from their past like horse manure, or old perfumes.
Perfumiers change recipes because CITES don't allow use of some animal derived products, and because of price, and changing health concerns with chemicals.
Primo Levi writes of post war searches for snake shit, which contains a urea concentrate which makes lipstick bind to the skin. Circus snake handlers laugh at him because it's sold on contract to the big perfume houses, not to random chemists.
