This short book is a myrmecological biography of the 18th-century naturalist and polymath, José Celestino Mutis (1732Ḱ8), and presents his observations on ant biology and behavior that have been pieced together from his diaries and various letters to and among colleagues. Mutis received his Ph.D. in Medicine in 1757 from the University of Seville and had a classical education in physics, chemistry, anatomy, astronomy, and botany. He arrived in what is now Bogotá, Colombia as the private physician of the viceroy of New Granada, Pedro Messía de la Cerda in 1761. In addition to his duties as physician and instructor of various sciences and mathematics, Mutis studied and catalogued the plant life in the vast region encompassed by the new Kingdom of Granada (now Costa Rica and Panama in Central America and Ecuador, Columbia, and Venezuela of the north of South America). Beginning in 1783 until his death, Mutis led the Royal Botanical Expedition of New Granada, which produced extensive lists, drawings, and specimens of the plant life of this megadiverse region of the world. He was an apostle and correspondent of Linnaeus and a contemporary and colleague of Alexander von Humboldt.