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- Systematics, biogeography, and character evolution of the legume tribe Fabeae with special focus on the middle-Atlantic island lineagesPublication . Schaefer, Hanno; Hechenleitner, Paulina; Santos-Guerra, Arnoldo; Sequeira, Miguel Menezes de; Pennington, R. Toby; Kenicer, Gregory; Carine, MarkBackground: Tribe Fabeae comprises about 380 legume species, including some of the most ancient and important crops like lentil, pea, and broad bean. Breeding efforts in legume crops rely on a detailed knowledge of closest wild relatives and geographic origin. Relationships within the tribe, however, are incompletely known and previous molecular results conflicted with the traditional morphology-based classification. Here we analyse the systematics, biogeography, and character evolution in the tribe based on plastid and nuclear DNA sequences. Results: Phylogenetic analyses including c. 70% of the species in the tribe show that the genera Vicia and Lathyrus in their current circumscription are not monophyletic: Pisum and Vavilovia are nested in Lathyrus, the genus Lens is nested in Vicia. A small, well-supported clade including Vicia hirsuta, V. sylvatica, and some Mediterranean endemics, is the sister group to all remaining species in the tribe. Fabeae originated in the East Mediterranean region in the Miocene (23–16 million years ago (Ma)) and spread at least 39 times into Eurasia, seven times to the Americas, twice to tropical Africa and four times to Macaronesia. Broad bean (V. faba) and its sister V. paucijuga originated in Asia and might be sister to V. oroboides. Lentil (Lens culinaris ssp. culinaris) is of Mediterranean origin and together with eight very close relatives forms a clade that is nested in the core Vicia, where it evolved c. 14 Ma. The Pisum clade is nested in Lathyrus in a grade with the Mediterranean L. gloeosperma, L. neurolobus, and L. nissolia. The extinct Azorean endemic V. dennesiana belongs in section Cracca and is nested among Mediterranean species. According to our ancestral character state reconstruction results, ancestors of Fabeae had a basic chromosome number of 2n=14, an annual life form, and evenly hairy, dorsiventrally compressed styles. Conclusions: Fabeae evolved in the Eastern Mediterranean in the middle Miocene and spread from there across Eurasia, into Tropical Africa, and at least seven times to the Americas. The middle-Atlantic islands were colonized four times but apparently did not serve as stepping-stones for Atlantic crossings. Long-distance dispersal events are relatively common in Fabeae (seven per ten million years). Current generic and infrageneric circumscriptions in Fabeae do not reflect monophyletic groups and should be revised. Suggestions for generic level delimitation are offered.
- Notas do Herbário Florestal do INIAV (LISFA): Fasc. XXXVIIPublication . Capelo, Jorge; Sequeira, Miguel Pinto da Silva Menezes de; Costa, José Carlos; Portela-Pereira, Estevão; Jardim, Roberto José Abreu; Neto, Carlos; Schaefer, Hanno; Espírito-Santo, Dalila; Lousã, Mário; Rivas-Martínez, Salvador
- Colonization and diversification shape species-area relationships in three Macaronesian archipelagosPublication . Price, Jonathan P.; Otto, Rüdiger; Sequeira, Miguel Menezes de; Kueffer, Christoph; Schaefer, Hanno; Caujapé-Castells, Juli; Fernández-Palacios, José MaríaAim: Species–area relationships (SARs) on oceanic archipelagos are shaped at least as much by speciation as by immigration–extinction dynamics. We examine three well‐studied Atlantic archipelagos to quantify the relative contributions of coloniza tion and diversification to individual and whole‐archipelago floras. Location: Three Macaronesian archipelagos: the Azores, Madeira and Canary Islands. Methods: We assessed the floras of all three archipelagos in order to compare SARs and numbers of endemic species with respect to the physical characteristics of each archipelago (geological age, isolation, and environmental diversity). Utilizing a large number of available phylogenies, we partitioned each flora into putative colonist lin eages. These were used to determine: (a) the number of original colonists of each archipelago, (b) degree of relatedness among these, and (c) the degree to which internal diversification contributes to species numbers for islands and archipelagos with different physical characteristics. Results: Archipelagos varied in the parameters of the SARs in relation to their phys ical characteristics. The Canarian and Madeiran floras demonstrate remarkably simi lar SARs with z values (slopes) near 0.3, while the Azorean flora exhibits fewer species per given area and a modest z value of 0.15. The Canarian and Madeiran endemic species are concentrated in a small number of diversifying lineages, whereas the Azorean endemics were mostly in anagenetic lineages (indicating mini mal internal diversification). Lineages that do not diversify within a given archipelago significantly tend not to diversify in others, whereas diversifying lineages tend to have more species in the Canarian flora when compared with related lineages in the others. Main conclusions: Although a strong independent effect of island area on species richness exists for the whole Macaronesian region, colonization and diversification are also influenced by geological age and environmental diversity of archipelagos, overriding characteristics of individual islands (“archipelago effect”). The “Azorean diversity enigma” likely results from a combination of geological youth, low environmental diversity and disproportionate human alteration.
- Is there solid evidence of widespread landscape disturbance in the Azores before the arrival of the Portuguese?Publication . Elias, Rui B.; Connor, Simon E.; Góis-Marques, Carlos A.; Schaefer, Hanno; Silva, Luís; Sequeira, Miguel M.; Moura, Mónica; Borges, Paulo A. V.; Gabriel, Rosalina