PART III
Island Evolution
The Macaronesian clade of Echium(Boraginaceae) consists of 28 endemic
species (two on Madeira, 23 on the Canaries, and three on the Cape Verde
islands), of which 26 exhibit woodiness. They derive from a single herbaceous
continental ancestor. The photograph shows Echium wildpretiissp.
trichosiphon, endemic to the summit scrub of La Palma (Canary Islands)
(with kind permission of Ángel Palomares).