The prisoner cichlid (Amatitlania nigrofasciata), also known as the zebra cichlid, is a species of cichlid fish native to Central America. The couple builds the nest and takes care of the eggs and parental care together. A study published in Proceedings of the Royal Society B by French researchers showed that when a female is separated from her partner, she becomes "pessimistic", as if heartbroken. She finds it harder to carry out tasks afterward. This study is the first demonstration in fish of