When I set out to write a book about the natural history of breasts, I knew I'd have to answer some awkward questions about my book topic. At a friend's book party, I entered a discussion with an elderly man who is slightly hard of hearing.
"What's your book about?" he politely asked.
"Breasts," I ventured.
"Breasts," I said louder. Some people turned to look at me.
"No, breasts!" By this time I was shouting and gesturing in an unmistakable way.
You get the idea.
Within my awkward topic of breasts, it soon became clear I'd have to tackle the awkward question of evolution. How did these wonders appear? At first, I thought this would be relatively straightforward. I figured that if all mammals had them, how complicated could it be? But this turned out to be one of the most contentious discussions in a book full of them. I soon learned that human breasts, in all their fatty, pendulous glory, are incredibly unique in the animal kingdom. Other primates have swollen mounds while lactating, but ours show up in puberty and stick around regardless of our lactational status.