The baobab trees (genus Adansonia) have attracted tremendous attention because of their striking shape and distinctive relationships with fauna 1 . These spectacular trees have also influenced human culture, inspiring innumerable arts, folklore and traditions. Here we sequenced genomes of all eight extant baobab species and argue that Madagascar should be considered the centre of origin for the extant lineages, a key issue in their evolutionary history 2,3 . Integrated genomic and ecological analyses revealed the reticulate evolution of baobabs, which eventually led to the species diversity seen today. Past population dynamics of Malagasy baobabs may have been influenced by both interspecific competition and the geological history of the island, especially changes in local sea levels. We propose that further attention should be paid to the conservation status of Malagasy baobabs, especially of Adansonia suarezensis and Adansonia grandidieri, and that intensive monitoring of populations of Adansonia za is required, given its propensity for negatively impacting the critically endangered Adansonia perrieri.

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Madagascar, a globally renowned biodiversity hotspot characterized by high rates of endemism, is one of the few remaining refugia for many plants and animal species. However, global climate change has greatly affected the natural ecosystem and endemic species living in Madagascar, and will likely continue to influence species distribution in the future. Madagascar is home to six endemic baobab ( Adansonia spp., Bombacoideae [Malvaceae]) species ( Adansonia grandidieri , A. suarezensis , A. madagascariensis , A. perrieri , A. rubrostipa , A. za ), which are remarkable and endangered plants. This study aimed to model the current distribution of suitable habitat for each baobab species endemic to Madagascar and determine the effect that climate change will have on suitable baobab habitat by the years 2050 and 2070. The distribution was modeled using MaxEnt based on locality information of 245 occurrence sites of six species from both online database and our own field work. A total of seven climatic variables were used for the modeling process. The present distribution of all six Madagascar's baobabs was largely influenced by temperature-related factors. Although both expansion and contraction of suitable habitat are predicted for all species, loss of original suitable habitat is predicted to be extensive. For the most widespread Madagascar baobab, A. za , more than 40% of its original habitat is predicted to be lost because of climate change. Based on these findings, we recommend that areas predicted to contract in response to climate change should be designated key protection regions for baobab conservation.

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Background Most tropical and subtropical plants are biotically pollinated, and insects are the major pollinators. A small but ecologically and economically important group of plants classified in 28 orders, 67 families and about 528 species of angiosperms are pollinated by nectar-feeding bats. From a phylogenetic perspective this is a derived pollination mode involving a relatively large and energetically expensive pollinator. Here its ecological and evolutionary consequences are explored. Scope and conclusions This review summarizes adaptations in bats and plants that facilitate this interaction and discusses the evolution of bat pollination from a plant phylogenetic perspective. Two families of bats contain specialized flower visitors, one in the Old World and one in the New World. Adaptation to pollination by bats has evolved independently many times from a variety of ancestral conditions, including insect-, bird- and non-volant mammal-pollination. Bat pollination predominates in very few families but is relatively common in certain angiosperm subfamilies and tribes. We propose that flower-visiting bats provide two important benefits to plants: they deposit large amounts of pollen and a variety of pollen genotypes on plant stigmas and, compared with many other pollinators, they are long-distance pollen dispersers. Bat pollination tends to occur in plants that occur in low densities and in lineages producing large flowers. In highly fragmented tropical habitats, nectar bats play an important role in maintaining the genetic continuity of plant populations and thus have considerable conservation value.

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Background and aims Baobab (Adansonia digitata) is a multi-purpose tree used daily by rural African communities. The present study aimed at investigating the level of morphometric and genetic variation and spatial genetic structure within and between threatened baobab populations from the three climatic zones of Benin. Methods A total of 137 individuals from six populations were analysed using morphometric data as well as molecular marker data generated using the AFLP technique. Key results Five primer pairs resulted in a total of 217 scored bands with 78.34 % of them being polymorphic. A two-level AMOVA of 137 individuals from six baobab populations revealed 82.37 % of the total variation within populations and 17.63 % among populations (P Conclusions The results indicate some degree of physical isolation of the populations collected in the different climatic zones and suggest a substantial amount of genetic structuring between the analysed populations of baobab. Sampling options of the natural populations are suggested for in or ex situ conservation.

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Knud Andersen (1912, Catalogue of the Chiroptera in the Collections of the British Museum: I. Megachiroptera, British Museum of Natural History, London) divided Old World fruitbats (family Pteropodidae) into the rousettine, cynopterine, epomophorine, eonycterine, and notopterine sections. The latter two sections comprise the subfamily Macroglossinae; members of this subfamily exhibit specializations for nectarivory (e.g., elongated, protrusible, brushy tongues) and cluster together in cladistic analyses based on anatomical characters. Other evidence, including single-copy DNA hybridization, suggests that macroglossines are either paraphyletic or polyphyletic; this implies that adaptations for pollen and nectar feeding evolved independently in different macroglossine lineages or were lost in nonmacroglossines after evolving in a more basal common ancestor. Hybridization data also contradict Andersen's phylogeny in providing support for an endemic African clade that includes representatives of three of Andersen's sections. Here, we present complete mitochondrial 12S rRNA and valine tRNA gene sequences for 20 pteropodids, including representatives of all of Andersen's sections, and examine the aforementioned controversies. Maximum likelihood, minimum evolution, and maximum parsimony analyses all contradict macroglossine monophyly and provide support for an African clade that associates Megaloglossus and Lissonycteris and those two with Epomophorus. In conjunction with the DNA hybridization results, there are now independent lines of molecular evidence suggesting: (i) convergent evolution of specializations for nectarivory, at least in Megaloglossus versus other macroglossines, and (ii) a previously unrecognized clade of endemic Africa taxa. Estimates of divergence time based on 12S rRNA and DNA hybridization data are also in good agreement and suggest that extant fruitbats trace back to a common ancestor 25 million to 36 million years ago.

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