From MacLean's, courtesy of Anne (thanks!):

In conversation: Florence Williams

On why we have breasts, what we don’t know about implants, and the future of breastfeeding

After reading a report about the presence of environmental toxins in breast milk in 2004, American journalist Florence Williams, who’d just had a child at the time, decided to have her own milk tested. She mailed samples to a lab. The results were astounding and unsettling: her toxin levels were exceptionally high. That propelled Williams to embark on an intense search that went well beyond her initial inquiries into the sociological, sexual and medical complexities of this organ. In Breasts: A Natural and Unnatural History, she provides a fascinating cultural and scientific tour of breasts through time—and what they might face in the future.

Q: You start the book by asking why humans have breasts. What did you find out from anthropologists, and how did their theories differ depending on their own sex?

A: It really surprised me that this topic is still so contentious. A lot of male anthropologists love to study the breast and they seem to be easily persuaded that the breast evolved as a sexual signal. But the more feminist [and more often female] anthropologists said it may be that breasts evolved not for men, but for the fitness of women and offspring.

Q: There is a compromise theory: breasts evolved to help women feed babies, and that made men love breasts.

A: Exactly.

Q: What do breasts signal to men?

A: The theory is that breasts are filled with information for potential mates about the fertility status of a woman, her age, how healthy she is: if the woman is young her breasts will be perky, and if she’s older her breasts will sag. I find this theory flawed. A woman’s breasts are biggest and perkiest while she’s pregnant and breastfeeding—and obviously she’s not a good mate at that moment if you’re just interested in your own offspring. And there are plenty of women who, after childbirth, continue to have nice, perky breasts. So breasts are an unreliable signal of age and fertility.

Q: Studies show female waitresses with large breasts get more tips, and busty diners get hit on more often. Is bigger always better?

A: In Western cultures, the studies do bear out that women tend to get more attention if they have bigger breasts. Many men really respond to big breasts. It’s hard to say whether that’s evolutionary driven or whether that’s our culture. Certainly our culture celebrates and is obsessed with big breasts.

Read the rest of the interview here.