A reader writes:

I am a behavioral ecologist. I actually study reproductive behavior in birds. I applaud the effort to gain understanding of human behavior by understanding animal behavior. But we really shouldn't stop too soon when following a thread in the natural world. I think the bird story stops a bit short.

Also underreported and underappreciated: that these promiscuous animals put quite a lot of effort into either preventing their partners from being promiscuous, or into hiding their own promiscuous behaviors from their partners.

Male birds may harrass their female partners if they catch the female spending too much time in another male's territory, or they may "mate guard" (remain glued to) their females during her fertile period.  Females in return may only seek these EPCs during very quick, pre-dawn forays into those neighbor's territories. Quick, and in total darkness? How sneaky is that?

So don't stop the comparison of animal sexual behavior to human sexual behavior too soon. Yes, we hanky-panky just like they do, but we are also living the lies, and dealing out the punishment, just like they do. That's why the terms "social" monogamy and "genetic" monogamy exist in science. For many individuals, it is advantageous to have multiple partners. But it is also advantageous to prevent their partners from having other partners.

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