Global patterns and drivers of phylogenetic structure in island floras

Islands are ideal for investigating processes that shape species assemblages because they are isolated &nbsp;and have discrete boundaries. Quantifying phylogenetic assemblage structure allows inferences in-situ speciation. Here, we link phylogenetic assemblage structure to island characteristics across 393 islands worldwide &nbsp;and 37,041 vascular plant species (representing angiosperms overall, palms and ferns). Physical and &nbsp;bioclimatic factors, especially those impeding colonization and promoting speciation, explained &nbsp;more &nbsp;variation &nbsp;in &nbsp;phylogenetic &nbsp;structure &nbsp;of &nbsp;angiosperms &nbsp;overall &nbsp;(49%) &nbsp;and &nbsp;palms &nbsp;(52%) &nbsp;than &nbsp;of &nbsp;ferns consistent with their dispersal- and speciation-related traits and climatic adaptations. Phylogenetic &nbsp;diversity was negatively related to isolation for palms, but unexpectedly it was positively related large-seeded, animal-dispersed palm family whereas colonization from biogeographically distinct in-situ among taxonomic groups on islands, which sheds light on the origin of insular plant diversity.</p

Ecosystem functions of oil palm plantations - a review

Oil palm plantations have expanded rapidly in the last decades. This large-scale land-use change has had great impacts on both the areas converted to oil palm and their surroundings. Howev-er, research on the impacts of oil palm agriculture is scattered and patchy, and no clear overview ex-ists. Here, we address this gap through a systematic and comprehensive literature review of all ecosys-tem functions in oil palm plantations. We compare ecosystem functions in oil palm plantations to those in forests as forests are often cleared for the establishment of oil palm. We find that oil palm planta-tions generally have reduced ecosystem functioning compared to forests. Some of these functions are lost globally, such as those to gas and climate regulation and to habitat and nursery functions. The most serious impacts occur when land is cleared to establish new plantations, and immediately after-wards, especially on peat soils. To variable degrees, plantation management can prevent or reduce losses of some ecosystem functions. The only ecosystem function which increased in oil palm planta-tions is, unsurprisingly, the production of marketable goods. Our review highlights numerous research gaps. In particular, there are significant gaps with respect to information functions (socio-cultural functions). There is a need for empirical data on the importance of spatial and temporal scales, such as the differences between plantations in different environments, of different sizes, and of different ages. Finally, more research is needed on developing management practices that can off-set the losses of ecosystem functions

The spatial scale of speciation and patterns of diversity

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The spatial scale of speciation and patterns of diversity

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Data from: Speciation has a spatial scale that depends on levels of gene flow

Area is generally assumed to affect speciation rates, but work on the spatial context of speciation has focused mostly on patterns of range overlap between emerging species rather than on questions of geographical scale. A variety of geographical theories of speciation predict that the probability of speciation occurring within a given region should (1) increase with the size of the region and (2) increase as the spatial extent of intraspecific gene flow becomes smaller. Using a survey of speciation events on isolated oceanic islands for a broad range of taxa, we find evidence for both predictions. The probability of in situ speciation scales with island area in bats, carnivorous mammals, birds, flowering plants, lizards, butterflies and moths, and snails. Ferns are an exception to these findings, but they exhibit high frequencies of polyploid and hybrid speciation, which are expected to be scale independent. Furthermore, the minimum island size for speciation correlates across groups with the strength of intraspecific gene flow, as is estimated from a meta‐analysis of published population genetic studies. These results indicate a general geographical model of speciation rates that are dependent on both area and gene flow. The spatial scale of population divergence is an important but neglected determinant of broad‐scale diversity patterns

Table A4 - Results of phylogeny search to check putative speciation events

Table A4 - Results of phylogeny search to check putative speciation event