Sexual relations between shepherds and the members of their flocks have existed for millennia, leading to the development of a certain type of love between them. The female llama, a ruminant related to the camel, is said by the local people in the Andean high plateau to weep with tears of jealousy when the herdsman replaces her with another female llama. The abandoned llama circles around the new couple, shedding tears of jealousy and sadness. I have had the opportunity to ask several shepherds about this. They told me that a replaced llama may gaze sadly at the new couple, but they had never seen one weep.“
An extract from : Tear Apparatus of Animals: Do They Weep? (in: The Ocular Surface, Volume 7, Issue 3, July 2009, Pages 121-127) by Juan Murube del Castillo MD PhD, professor emeritus of ophthalmology, at the University of Acalà, Madrid, Spain.