The chapter presents multiple studies from various disciplines that investigated evolutionary perspectives on sexual love. It shows how sexual dimorphism and mating strategies evolved and diversified across animal species, setting the basis for the emergence and evolution of sexual love. The author explains how sexual love became a mating device supporting animal and human mating as sexual reproduction. The following sections provide an extensive review of research findings that demonstrated the varieties of mating systems and love across species of plants, birds, animals, and especially early humans. Further sections show how similarities and differences between mates, as well as conditioning and learning mechanisms, taught animals to sexually love each other, whether we call this instinctual or not.