In article ,
Iris Cohen wrote:
Some years ago I had a stapeliad type plant, I forget the name, whose flowers
smell exactly like cheese. Presumably its pollinator was some kind of cheese
fly. My question: mother animals in the wild don't leave their milk lying
around to turn into cheese. I understand cheese is strictly a human discovery.
So how did a flower evolve that smells like cheese?

It's more a rancid and/or putrid odor. Strong cheeses develop their
characteristic smells from oxidation of fats (rancidity) and
decomposition of proteins (putridity). Both these classes of odor are
attractive to insects which lay eggs in carrion.

When I put my stapelias outdoors in the summer they often bloom with
their characteristic speckled and streaked stinking flowers, covered
with hairs, looking like the swollen corpse of a dead rodent. Flies
lay eggs all over them. This system makes them wait until their outdoor
summer vacation to bloom. Indoors, they are socially unacceptable.

I've noticed that different species have somewhat different smells,
not that I'm a connoisseur of fragrances of dungs and carrion!