For ex situ conservation to be successful, the animals being released ought to have a behavioural repertoire as close as possible to that of their wild conspecifics. However, captive conditions may lead to unintentional changes in the animals.

The aim of the present study was to investigate the development of social behaviour, morphology and the possibility of neoteny in two captive populations of red jungle fowl ( Gallus gallus L), one originating from Copenhagen zoo (COP) and one from Götala research station (GOT) and one domesticated strain of White Leghorn layers ( Gallus gallus domesticus L) (WL). The animals were hatched and reared under identical conditions in order to eliminate environmental effects. 37 birds (14 COP, 13 GOT and 11 WL) were tested in a group observation test and a social attachment test. Morphological measurements were also done.

The results showed morphological differences between the populations in size, shape and development of morphological traits. No significant differences in social behaviours were found, but there were indications of developmental differences in aggressive behaviours, sexual maturation and social distance. The social attachment revealed that the birds reacted differently in an isolated situation which may be   an alteration of thresholds for performing certain behaviours . No obvious signs of neoteny as a result of domestication were found.

In conclusion, since the environment was identical, the differences found were most likely due to genetically differences which may reflect different aspects of the birds’ ancestors.