Four-leaf clovers are traditional emblems of good luck. Two-headed sheep, five-legged frogs, or persons with six-fingered hands, by contrast, are more likely to be considered repugnant monsters, or “freaks of nature.” Such alienation was not always the case. In sixteenth-century Europe, such “monsters,” like the four-leaf clover today, mostly elicited wonder and respect. People were fascinated with natural phenomena just beyond the edge of the familiar. Indeed, that emotional response—at that juncture in history—helped foster the emergence of modern science. Wonder fostered investigation and, with it, deeper understanding of nature. One might thus well question a widespread but generally unchallenged belief about biology—what one might call a sacred bovine: that emotions can only contaminate science with subjective values. Indeed, delving into how “monsters” once evoked wonder might open a deeper appreciation of how science works today. Consider the case of Petrus Gonsalus, born in 1556 (Figure 1.1). As one might guess from his portrait, Gonsalus (also known as Gonzales or Gonsalvus) became renowned for his exceptional hairiness. He was a “monster”: someone—like dwarves, giants, or conjoined twins—with a body form conspicuously outside the ordinary. But, as his courtly robe might equally indicate, Gonsalus was also special. Gonsalus was born on Tenerife, a small island off the west coast of Africa. But he found a home in the court of King Henry II. Once there, he became educated. “Like a second mother France nourished me from boyhood to manhood,” he recollected, “and taught me to give up my wild manners, and the liberal arts, and to speak Latin.” Gonsalus’s journey from the periphery of civilization to a center of power occurred because he could evoke a sense of wonder. Eventually, he moved to other courts across Europe. Wonder was widely esteemed. For us, Gonsalus may be emblematic of an era when wonder flourished. In earlier centuries monsters were typically viewed as divine portents, or prodigies. Not that they were miracles. The course of nature seemed wide enough to include them.