In the 18th and 19th centuries the Eurasian Collared Dove Streptopelia decaocto was widely considered to be the wild ancestor of the domesticated Barbary Dove (domestic S. risoria), and even following its recognition as a species its taxonomic status was a source of confusion. Since 1900, and the species' massive geographic expansion (both naturally and by introduction) the two taxa have occasionally met. The resultant hybridisation is probably the cause of the large number of Eurasian Collared Doves with the aberrant pale colour of Barbary Doves in areas where hybridisation has occurred.