Effect of cross-rearing on species identification in zebra fish and pearl danios.

Zebra fish and pearl danios were either cross-reared or raised with conspecifics and tested as adults for species preference over 4 days. Subjects were then placed with conspecifics by group for 30 days and retested over 2 days. Initial testing showed less preference (species identification) for conspecifics by cross-reared subjects and less conspecific preference by pearls than zebras. At retesting pearls showed a great increase in preference for conspecifics whereas zebras showed little change.