In Chimpanzee Politics: Power and Sex among Apes (1982), Frans de Waal discusses reconciliation, but he’s not talking about human beings who are making up after fighting. Rather, de Waal is describing the reconciliation he has observed in communities of chimpanzees:
Sometimes the maneuver is fairly obvious. Within a minute of a fight having ended the two former opponents may rush towards each other, kiss, and embrace long and fervently and then proceed to groom each other. But sometimes this kind of emotional contact takes place hours after a conflict. When I observed very carefully, I saw that the tension and hesitancy remained as long as the opponents had not reconciled their differences. Then suddenly the ice would break in one of the chimpanzees would approach the other . . . currently, there is no doubt that primates are capable of reconciling; the question rather is under which circumstances they do so. (Page 27, 29).
(The above photo and caption are from Chimpanzee Politics)
Most fundamentalists would argue that we should not study “animals” in order to draw any conclusions about human behavior, as though human beings are not animals. They argue that you can’t draw conclusions about humans based upon an “animal species.” They then proceed to make their own wild conclusions about human animals based upon zero other animal species. Their conclusions are mostly ad hoc and a priori, often completely contradicted by scientific observations. Fundamentalists thus create souls and heavens completely out of their embellished imaginations and their apocryphal old book. In this way, fundamentalists are blindered and unrelenting armchair anthropologists/primatologists/zoologists.
(This photo of these chimpanzee youngsters and the caption are also from Chimpanzee Politics)
De Waal argues that claims of human uniqueness “are a bit like advertisements for squirrel proof bird feeders,” in that both claims are way overstated. He argues (in all of his books) that there is an obvious continuity between humans and chimpanzees to anyone who cares to look.
The time has come to define the human species against the backdrop of the vast common ground we share with other life forms. Instead of being tied to how we are unlike any animal, human identity should be built around how we are animals that have taken certain capacities a significant step farther. We and other animals are both similar and different, and the former is the only sensible framework within which to flesh out the latter.
(The Ape and the Sushi Master (2001), page 362). Why else start with the assumption that there is a strong continuity running from human behavior and behavior of other animals? See here, here, here, here, here and here.