fact, we would rather not experience many of the smells of city living.
We refrigerate our food, but we don’t refrigerate our garbage. Once
proud, this superpower is devolving.
Certainly, we are not the sensory animals we used to be, and
neither are the animals we’ve domesticated. Wolves outperform dogs
in tests of general intelligence. Domestic cats differ from wild cats in
some interesting ways having to do with skull size and foraging
smarts. Which raises the provocative question: what about us? Are we
self-domesticating? Of course, argues Harvard primatologist Richard
Wrangham, who makes a particular case for humans becoming less
aggressive as we’ve evolved into larger social groups. Our brain size
and musculature peaked during the last ice age. Our teeth have gotten
smaller, our long-distance vision worse. Since we settled down in
farming communities around 10,000 years ago, we’ve grown weaker,
and no doubt in some ways, dumber. The fast-firing sensory neurons
we needed to stay alive in dynamic wild environments have, shall we
say, relaxed. Of course we’ve gotten good at some things, like
negotiating traffic circles and thumb eye coordination for text-
messaging. Scientists have shown that the hippocampi of London
cabdrivers grow as they learn to map the city. Our individual brains
are adapting to handle modern life, even from one year to the next,
but that reflects flexibility, not evolution. In the mismatch between
our current lives and our current brains, the primary victim is our
paleolithic nervous system. No wonder, then, that when something
smells really great we get happy. It’s as though we’ve momentarily
stepped through the wardrobe.
SMELLS HOLD POWER over us because the nose is a direct pathway to
the brain. This is why some drugs are administered nasally.
Molecules of a certain size that enter through the nose bypass the
blood brain barrier and march right into the gray matter. While this
shortcut is convenient for pharmaceutical companies, it’s less helpful