Why is nasal congestion is like an erection inside your nose? What are the nonsexual health benefits of orgasm? And why, pray tell, are the rats in Dr. Ahmed Shafik's laboratory all wearing polyester pants? The answers to these questions and many more (yet unasked) questions are offered up in Mary Roach's recent work of scientific inquiry, Bonk, a riveting and often hilarious romp in the world of sex.

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