For some unknown reason, I was born without a sense of smell. In her book "A Natural History of the Senses" Diane Ackerman suggests "smumb" as an appropriate moniker for my condition. ("There goes Chet. He's smumb.").
The official name is anosmia.
In recent years, researchers have begun to pay more attention to the sense of smell. For example, we now know that mice have about 1200 genes for scent receptors, most of them in full working order.
Humans, by contrast, have only about 1000 smell receptor genes, and the greater part of these have been put out of action by deleterious mutations.
It seems that with our big brains and keen color vision modern humans don't rely as much on the nose as did our mammalian ancestors.
So rather than smumb, I now think of myself as highly evolved.