Research in Macaronesia has led to substantial advances in ecology, evolution and conservation biology. We review the scientific developments achieved in this region, and outline promising research avenues enhancing conservation. Some of these discoveries indicate that the Macaronesian flora and fauna are composed of rather young lineages, not Tertiary relicts, predominantly of European origin. Macaronesia also seems to be an important source region for back-colonisation of continental fringe regions on both sides of the Atlantic. This group of archipelagos (Azores, Madeira, Selvagens, Canary Islands, and Cabo Verde) has been crucial to learn about the particularities of macroecological patterns and interaction networks on islands, providing evidence for the development of the General Dynamic Model of oceanic island biogeography and subsequent updates. However, in addition to exceptionally high richness of endemic species, Macaronesia is also home to a growing number of threatened species, along with invasive alien plants and animals. Several innovative conservation and management actions are in place to protect its biodiversity from these and other drivers of global change. The Macaronesian Islands are a well-suited field of study for island ecology and evolution research, mostly due to its special geological layout with 40 islands grouped within five archipelagos differing in geological age, climate and isolation. A large amount of data is now available for several groups of organisms on and around many of these islands. However, continued efforts should be made toward compiling new information on their biodiversity, to pursue various fruitful research avenues and develop appropriate conservation management tools.

Recent phylogeographical analyses using mitochondrial DNA (mtDNA) sequences indicate that the Tarentola geckos from the Cape Verde archipelago origin

Dietary studies can reveal valuable information on how species exploit their habitats and are of particular importance for insular endemics conservation as these species present higher risk of extinction. Reptiles are often neglected in island systems, principally the ones inhabiting remote areas, therefore little is known on their ecological networks. The Selvagens gecko Tarentola (boettgeri) bischoffi, endemic to the remote and integral reserve of Selvagens Archipelago, is classified as Vulnerable by the Portuguese Red Data Book. Little is known about this gecko’s ecology and dietary habits, but it is assumed to be exclusively insectivorous. The diet of the continental Tarentola species was already studied using classical methods. Only two studies have used next-generation sequencing (NGS) techniques for this genus thus far, and very few NGS studies have been employed for reptiles in general. Considering the lack of information on its diet and the conservation interest of the Selvagens gecko, we used morphological and DNA metabarcoding approaches to characterize its diet. The traditional method of morphological identification of prey remains in faecal pellets collected over a longer period was compared with metabarcoding of samples collected during rapid surveys. Molecular results revealed that this species is a generalist, feeding on invertebrate, plant and vertebrate items, whereas the morphological approaches were unable to detect the latter two. These results opened up new questions on the ecological role of the Selvagens gecko that deserves to be further explored, such as the possible predation on seabirds, plant services or trophic competition with the sympatric Madeira lizard Teira dugesii. Metabarcoding identified a greater diversity of dietary items at higher taxonomic resolution, but morphological identification enabled calculation of relative abundances and biomasses of ingested arthropods, and detected a dietary shift on invertebrate preys between seasons. Results of this study highlight the global applicability of rapid metabarcoding surveys for understudied taxa on remote islands that are difficult to access. We recommend using the metabarcoding approach, even if ‘speedy’ sampling only is possible, but we must highlight that disregarding long-term ecological data may lead to ‘hasty’ conclusion.