4
" Absorption of parental care into adult human relationships is evident from the widespread use of infantile names (such as "baby") for mates and lovers, and the special high-pitched voice that we reserve for both young children and intimate partners. In this context, Eibl-Eibesfeldt mentions the kiss, which probably derives from mouth-to-mouth feeding of masticated food. Kissing without any transfer of food is an almost universal human expression of love and affection, which, according to the ethologist, resembles kiss feeding "with one partner playing the accepting part by opening the mouth in a babyish fashion and the other partner performing tongue movements as if to pass food." Significantly, chimpanzees both kiss feed their young and kiss between adults. A close relative of the chimpanzee, the bonobo, even tongue-kisses. "
― Frans de Waal , Good Natured: The Origins of Right and Wrong in Humans and Other Animals
9
" If carnivory was indeed the catalyst for the evolution of sharing, it is hard to escape the conclusion that human morality is steeped in animal blood. When we give money to begging strangers, ship food to starving people, or vote for measures that benefit the poor, we follow impulses shaped since the time our ancestors began to cluster around meat possessors. At the center of the original circle we find aprize hard to get but desired by many, a situation that remains essentially unchanged. In the course of human evolution and history, this small, sympathetic circle grew steadily to encompass all of humanity— if not in practice then at least in principle. Some philosophers, such as Peter Singer in The Expanding Circle, even feel that all creatures under the sun deserve to be included, and that animals should therefore never be used for research, entertainment, or human consumption. Given the circle's proposed origin, it is profoundly ironic that its expansion should culminate in a plea for vegetarianism. "
― Frans de Waal , Good Natured: The Origins of Right and Wrong in Humans and Other Animals