 However more recent work has shown that these plants are adequately pollinated by non-specialist flower visiting birds, particularly the Canary Islands chiffchaff ("Phylloscopus canariensis"), and the Canary Sardinian warbler ("Sylvia melanocephala leucogastre") (Olesen 1985, Ollerton et al.2008), and in fact show some specific adaptations to infrequent pollination by these birds, such as extended flower lifespans (Ollerton et al.2008), and a hexose-dominated sugar ratio in the composition of the nectar (Dupont et al.