In addition to research in primates, biologists are beginning to explore reconciliation in other animals. Up until recently, the literature dealing with reconciliation in non-primates have consisted of anecdotal observations and very little quantitative data. Although peaceful, post-conflict behavior had been documented going back to the 1960s, it was not until 1993 that Rowell made the first explicit mention of reconciliation in feral sheep. Reconciliation has since been documented in spotted hyenas, lions, dolphins, dwarf mongooses, domestic goats, and domestic dogs.