are closely related species. Until recently it was thought there was a single species (Hedera helix), but recent studies have shown that there are several species that differ mainly by microscopic details of the hairiness of the buds. The patterns of speciation in Hedera are the product of vicariance, resulting from the fragmentation of the geographical range of a common ancestor that was more widespread during the Tertiary. References canariensis Flora of the Canary Islands Flora of North Africa Medicinal plants of Africa Garden plants of Africa Groundcovers Vines