Jon Cohen investigates what is perhaps the most humane form of animal testing:

[Pascal Gagneux is trying] to unlock one of the riddles of human infertility: does sperm sometimes have components that undermine its ability to fertilize an egg? Perhaps the differences between chimp and human sperm can help explain why humans miscarry nearly 50 percent of all conceptions, while chimps seem rarely to lose an embryo or fetus.

To get at such questions, Gagneux has spent many hours fashioning devices to coax sperm from chimpanzees. He began by sculpting a silicone version of a female chimp’s rear end. But the male chimpanzees at the Primate Foundation of Arizona that were recruited to help with the project did not see it that way, and the model sat unmolested on a counter. “It’s a nice chimp butt, but I thought it was a bonobo butt when I first saw it,” Jim Murphy, the foundation’s colony manager at the time, admitted to me when I visited a few years ago. “Maybe that’s why they don’t like it.”

The scientists eventually found a way to entice the chimps with a Penrose drain, and rewarded them with M&Ms. You'll have to read the whole piece for more details. For me, it's fascinating that humans evolved somehow to be more likely to miscarry than chimps, i.e. from the Thomist point of view, that nature reveals that God has a lesser view of human life than chimp life.

More human souls are lost in nature than chimp souls. Over to you, Robby George.

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