(Holt, 289 pages, $25)

“Chemistry” really is the best way to explain love’s predilections, says evolutionary biologist Helen Fisher. Physical beauty helps spark the fire, but growing evidence shows that temperament is a critical element of sexual attraction, and that temperament is largely the product of innate brain chemistry. In Fisher’s view, each of us falls into one of four temperament types. If your dopamine levels run high, you’re an “Explorer”—adventurous and highly creative. Elevated serotonin levels create ­conscientious “Builders,” estrogen produces idealistic “Negotiators,” and testosterone yields hard-charging “Directors.” Surveys that Fisher has distributed to millions of people show an unmistakable pattern in each type’s romantic preference. Explorers click with other Explorers. Builders bond with other Builders. Negotiators, meanwhile, fancy Directors, and vice versa.

You may be wondering how one’s type is determined in these studies, said Graham Lawton in New Scientist. Fisher, a Rutgers University professor well versed in the neurochemistry of personality, devised a questionnaire meant to sort individuals into her four categories. She first distributed it to 40,000 customers of the online dating site, and was able to track the love lives of 28,000 of those respondents. It was among them that the bold lines of dating patterns first surfaced. Quick-sorting can work, too, said Kate Abbott in the London Guardian. Fisher found that most Directors used “intellectual” as a one-word description of themselves. Negotiators preferred “passionate,” and Builders talked a lot about “family.” Another intriguing tell, said Belinda Luscombe in Time, is that “the ring fingers of Directors are longer than their index fingers.”

“Can we all really be typed so easily?” said Caroline Leavitt in The Boston Globe. Contemplating Fisher’s theories may make some readers “a little uneasy.” But she’s been studying the subject of attraction for decades, and many of her side journeys are fascinating. She recasts an old-fashioned kiss, for instance, as “a blast” of shared information, in which each partner is using one of the body’s most sensitive data receptors to pick up messages about taste, smell, touch, and temperature. “Better loving through chemistry?” You could call it that.