Populations west of L Chad sometimes awarded separate subspecies, bornuensis.
Domesticated form, sometimes referred to as Streptopelia risoria, has been subject of many studies on genetics, psychology, ethology, neurophysiology and notably endocrinology.
The following 2 subspecies are recognised:
roseogrisea (Sundevall, 1857) - South-western Mauritania and Senegambia east through Mali, Niger, Chad and Sudan to western Ethiopia.
arabica (Neumann, 1904) - Coastal Eritrea and Somalia, and Arabia from Jiddah to Aden (southern Yemen).
The Reader's Digest Book of British Birds 1980, 3rd Edition, Drive Publications Ltd ISBN 0 340 25308 8
Birds in Colour Campbell, B., 1960, Penguin Books Ltd
The Pocket Guide to Nest and Eggs Fitter, R.S.R., 1954, Collins
RSPB Handbook of British Birds Holden, P., Cleeves, T., 2002, A & C Black ISBN 0 7136 5713 8
Birds of Britain and Europe Sterry, P., et al., 2001, AA Publishing ISBN 0 7495 3068 5
The Popular Handbook of British Birds Hollom, P.A.D., 1973, H.F. & G. Witherby Ltd ISBN 0 85493 002 7