RT info:eu-repo/semantics/article
T1 Colonization and diversification shape species–area relationships in three Macaronesian archipelagos
A1 Price, Jonathan
A1 Otto, Rüdiger
A1 Menezes de Sequeira, Miguel
A1 Kueffer, Christoph
A1 Schaefer, Hanno
A1 Fernández-Palacios, José María
A1 Caujapé‑Castells, Juli
K1 Azores
K1 Biodiversity
K1 Canary islands
K1 Flora
K1 Macaronesia
K1 Madeira
K1 Phylogeny
K1 Species–area relationship
AB Aim: Species–area relationships (SARs) on oceanic archipelagos are shaped at leastas much by speciation as by immigration–extinction dynamics. We examine threewell‐studied Atlantic archipelagos to quantify the relative contributions of colonizationand diversification to individual and whole‐archipelago floras.Location: Three Macaronesian archipelagos: the Azores, Madeira and CanaryIslands.Methods: We assessed the floras of all three archipelagos in order to compare SARsand numbers of endemic species with respect to the physical characteristics of eacharchipelago (geological age, isolation, and environmental diversity). Utilizing a largenumber of available phylogenies, we partitioned each flora into putative colonist lineages.These were used to determine: (a) the number of original colonists of eacharchipelago, (b) degree of relatedness among these, and (c) the degree to whichinternal diversification contributes to species numbers for islands and archipelagoswith different physical characteristics.Results: Archipelagos varied in the parameters of the SARs in relation to their physicalcharacteristics. The Canarian and Madeiran floras demonstrate remarkably similarSARs with z values (slopes) near 0.3, while the Azorean flora exhibits fewerspecies per given area and a modest z value of 0.15. The Canarian and Madeiranendemic species are concentrated in a small number of diversifying lineages,whereas the Azorean endemics were mostly in anagenetic lineages (indicating minimalinternal diversification). Lineages that do not diversify within a given archipelagosignificantly tend not to diversify in others, whereas diversifying lineages tend to have more species in the Canarian flora when compared with related lineages in theothers.Main conclusions: Although a strong independent effect of island area on speciesrichness exists for the whole Macaronesian region, colonization and diversificationare also influenced by geological age and environmental diversity of archipelagos,overriding characteristics of individual islands (“archipelago effect”). The “Azoreandiversity enigma” likely results from a combination of geological youth, low environmentaldiversity and disproportionate human alteration.
YR 2018
FD 2018
LK http://riull.ull.es/xmlui/handle/915/16999
UL http://riull.ull.es/xmlui/handle/915/16999
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 09-nov-2024