For all researches, please visit our "Peer-reviewed publications" page.
Jia S, Zhang M, Raab-Straube E, Thulin M (2016)
Evolutionary history of Gymnocarpos (Caryophyllaceae) in the arid regions from North Africa to Central Asia
Biological Journal of the Linnean Society.
Gymnocarpos has only about ten species distributed in the arid regions of Asia and Africa, but it exhibits a geographical disjunction between eastern Central Asia and western North Africa and Minor Asia. We sampled eight species of the genus and sequenced two chloroplast regions (rps16 and psbB–psbH), and the nuclear rDNA (ITS) to study the phylogeny and biogeography. The results of the phylogenetic analyses corroborated that Gymnocarpos is monophyletic, in the phylogenetic tree two well supported clades are recognized: clade 1 includes Gymnocarpos sclerocephalus and G. decandrus, mainly the North African group, whereas clade 2 comprises the remaining species, mainly in the Southern Arabian Peninsula. Molecular dating analysis revealed that the divergence age of Gymnocarpos was c. 31.33 Mya near the Eocene and Oligocene transition boundary, the initial diversification within Gymnocarpos dated to c. 6.69 Mya in the late Miocene, and the intraspecific diversification mostly occurred during the Quaternary climate oscillations. Ancestral area reconstruction suggested that the Southern Arabian Peninsula was the ancestral area for Gymnocarpos. Our conclusions revealed that the aridification since mid-late Miocene significantly affected the diversification of the genus in these areas.
Keywords: 2016, CN, China, DE, GBIF_used, Germany, SE, Sweden, phylogenetic analysis, phylogenetics
Lagomarsino L, Condamine F, Antonelli A, Mulch A, Davis C (2016)
The New phytologist.
The tropical Andes of South America, the world's richest biodiversity hotspot, are home to many rapid radiations. While geological, climatic, and ecological processes collectively explain such radiations, their relative contributions are seldom examined within a single clade. We explore the contribution of these factors by applying a series of diversification models that incorporate mountain building, climate change, and trait evolution to the first dated phylogeny of Andean bellflowers (Campanulaceae: Lobelioideae). Our framework is novel for its direct incorporation of geological data on Andean uplift into a macroevolutionary model. We show that speciation and extinction are differentially influenced by abiotic factors: speciation rates rose concurrently with Andean elevation, while extinction rates decreased during global cooling. Pollination syndrome and fruit type, both biotic traits known to facilitate mutualisms, played an additional role in driving diversification. These abiotic and biotic factors resulted in one of the fastest radiations reported to date: the centropogonids, whose 550 species arose in the last 5 million yr. Our study represents a significant advance in our understanding of plant evolution in Andean cloud forests. It further highlights the power of combining phylogenetic and Earth science models to explore the interplay of geology, climate, and ecology in generating the world's biodiversity.
Keywords: Andes, Lobelioideae, Neotropics, biodiversity hotspot, climate change, diversification, pollination syndromes, rapid radiation
Nylinder S, Razafimandimbison S, Anderberg A (2016)
Journal of Biogeography.
Aim We investigated the historical biogeography of the Inuleae–Plucheinae (Asteraceae), a group of arid-adapted plants with partly unresolved generic circumscriptions, in order to understand its origin and spatiotemporal evolutionary history in relation to the Cenozoic climate shifts. Location Global, with highest species diversity in the Southern Hemisphere. Methods The spatiotemporal biogeography of the Plucheinae was estimated by both a discrete method using a set of general distribution areas, and a relaxed random walk based on extant species distributions. The topology was time calibrated using a combination of secondary node ages and secondary derived rates for included loci. Results Our results indicate the median age of the Plucheinae to be approximately 15.4 Ma. The biogeographical analyses infer an ancestral origin in southern Africa, with the relaxed random walk analysis narrowing the uncertainty down to an area reaching from coastal Namibia to the western Kalahari. Africa was colonized in a (south)western–(north)eastern direction following the spread of arid habitats. Ancestral representatives of the Plucheinae colonized South America on at least three separate occasions (13.0–4.0, 4.3–3.1 and 4.1–3.7 Ma), with one subsequent spread to North America. Australia was colonized three times between 3.6 and 0.4 Ma. Madagascar and the Mascarenes were colonized at least seven times. Main conclusions The origin of the Plucheinae is estimated to the Namib region, with early speciations and radiations concurring with the timing of aridification of southern Africa, following the increase in strength of the Antarctic Circumpolar Current and subsequent formation of the Benguela Upwelling at c. 11.8 Ma. The current biogeographical distribution of the Plucheinae is best explained by several Neogene long-distance dispersal events from tropical Africa
Keywords: Africa, Asteraceae, Namibia, arid environment, biogeography, dispersal, molecular dating
Sanín M, Kissling W, Bacon C, Borchsenius F, Galeano G, Svenning J et al. (2016)
The Neogene rise of the tropical Andes facilitated diversification of wax palms ( Ceroxylon : Arecaceae) through geographical colonization and climatic niche separation
Botanical Journal of the Linnean Society.
he tropical Andes are a biodiversity hotspot, partly due to their rich and complex floristic composition. A fundamental question regarding this outstanding biodiversity is what role the Andean orogeny has played in species diversification. Ceroxylon is a genus of endemic Andean palms that stands out in the palm family (Arecaceae) due to its adaptation to cold, mountainous environments. Here, we reconstruct the biogeography and climatic preference of this lineage to test the hypothesis that Andean uplift allowed diversification by providing suitable habitats along climatic and elevational gradients. Ancestral areas were reconstructed under a model allowing for founder-event speciation and climatic niches were inferred from climatic variables at present-day occurrences of all species. Niche evolution in a phylogenetic framework was evaluated by testing differences between the climatic niches of clades. Our analyses identified four main clades, with a general pattern of diversification through geographical colonization from south to north after the Pliocene uplift of the northern Andes. Adaptation to low temperatures was conserved at the generic level, with climatic niche differentiation among clades along elevational temperature gradients. We conclude that the Neogene Andean uplift has facilitated the diversification of this iconic plant group via opportunities for geographical migration and separation within its climatic niche
Keywords: Miocene, Neotropics, cold adaptation, niche shift, phylogenetic niche conservatism, range expansion
Edler D, Guedes T, Zizka A, Rosvall M, Antonelli A (2015)
Biogeographical regions reveal how species are spatially grouped and therefore are important units for conservation, historical biogeography, ecology and evolution. Several methods have been developed to identify bioregions based on species distribution data rather than expert opinion. One approach successfully applies network theory to simplify and highlight the underlying structure in species distributions data. However, there are no tools that make this methodology simple and efficient to use. Here we present Infomap Bioregions, an interactive web application that inputs species distribution data and generates bioregion maps. Species distributions may be provided as georeferenced point occurrences or range maps, and can be of local, regional or global scale. The application uses a novel adaptive resolution method to make best use of often incomplete species distribution data. The results can be downloaded as vector graphics, shapefiles or in table format. We validate the tool by processing large datasets of publicly available species distribution data of the world's amphibians using species ranges, and mammals using point occurrences. Potential applications include ancestral range reconstructions in historical biogeography and identification of indicator species for targeted conservation.
Keywords: Miocene, Neotropics, cold adaptation, niche shift, phylogenetic niche conservatism, range expansion
Fuentes-Hurtado M, Hof A, Jansson R (2015)
Paleodistribution modeling suggests glacial refugia in Scandinavia and out-of-Tibet range expansion of the Arctic fox
Ecology and Evolution.
Quaternary glacial cycles have shaped the geographic distributions and evolution of numerous species in the Arctic. Ancient DNA suggests that the Arctic fox went extinct in Europe at the end of the Pleistocene and that Scandinavia was subsequently recolonized from Siberia, indicating inability to track its habitat through space as climate changed. Using ecological niche modeling, we found that climatically suitable conditions for Arctic fox were found in Scandinavia both during the last glacial maximum (LGM) and the mid-Holocene. Our results are supported by fossil occurrences from the last glacial. Furthermore, the model projection for the LGM, validated with fossil records, suggested an approximate distance of 2000 km between suitable Arctic conditions and the Tibetan Plateau well within the dispersal distance of the species, supporting the recently proposed hypothesis of range expansion from an origin on the Tibetan Plateau to the rest of Eurasia. The fact that the Arctic fox disappeared from Scandinavia despite suitable conditions suggests that extant populations may be more sensitive to climate change than previously thought.
Keywords: Arctic fox, Fennoscandia, Out-of-Tibet hypothesis, ecological niche modeling, last glacial maximum, refugia
Gough L, Sverdrup-Thygeson A, Milberg P, Pilskog H, Jansson N, Jonsell M et al. (2015)
Ecology and Evolution.
Ancient trees are considered one of the most important habitats for biodiversity in Europe and North America. They support exceptional numbers of specialized species, including a range of rare and endangered wood-living insects. In this study, we use a dataset of 105 sites spanning a climatic gradient along the oak range of Norway and Sweden to investigate the importance of temperature and precipitation on beetle species richness in ancient, hollow oak trees. We expected that increased summer temperature would positively influence all wood-living beetle species whereas precipitation would be less important with a negligible or negative impact. Surprisingly, only oak-specialist beetles with a northern distribution increased in species richness with temperature. Few specialist beetles and no generalist beetles responded to the rise of 4°C in summer as covered by our climatic gradient. The negative effect of precipitation affected more specialist species than did temperature, whereas the generalists remained unaffected. In summary, we suggest that increased summer temperature is likely to benefit a few specialist beetles within this dead wood community, but a larger number of specialists are likely to decline due to increased precipitation. In addition, generalist species will remain unaffected. To minimize adverse impacts of climate change on this important community, long-term management plans for ancient trees are important.
Keywords: Beetles, climate gradient, coleoptera, precipitation, saproxylic, temperature
Hof A, Svahlin A (2015)
The potential effect of climate change on the geographical distribution of insect pest species in the Swedish boreal forest
Scandinavian Journal of Forest Research 1-11.
ABSTRACTWith the expected rising temperatures, outbreaks of insect pests may be more frequent, which can have large consequences on forest ecosystems and may therefore negatively affect the forestry sector. In order to be better able to predict where, but not if, outbreaks may occur in future we investigated the potential future (2070) geographical distribution of 30 prospective insect pest species (Coleoptera and Lepidoptera) by applying species distribution modelling. We also assessed the geographical extent to which the boreal forest in Sweden may be affected. We found that numerous species may experience large increases in their potential distribution in future, which may result in outbreaks in “new” areas. It is therefore likely that more trees will be infested by pests in future, which may have large implications for the Swedish forestry sector.
Keywords: Norway spruce, Scots pine, climate change, forestry, insects, pests, species distribution modelling
Kullander S, Rahman M, Norén M, Mollah A (2015)
Why is Pseudosphromenus cupanus (Teleostei: Osphronemidae) reported from Bangladesh, Indonesia, Malaysia, Myanmar, and Pakistan?
Zootaxa 3990(4) 575-83.
The native distribution of the small labyrinth fish species Pseudosphromenus cupanus includes southern India and Sri Lanka. According to literature it has a range including also Pakistan, Bangladesh, Myanmar, Malaysia, and Indonesia (Sumatra) but there are no voucher specimens or reliable observations from those areas. The distribution record of P. cupanus was inflated partly by including P. dayi as a synonym. Pseudosphronemus dayi is native to the Western Ghats in India, but the origin of the aquarium importation in 1907 was reported as both Cochin (=Kochi) and Malacca (=Malaysia), the latter locality obviously in error. The basis for the Sumatra record is an obviously mislabeled sample of P. dayi from Pulau Weh close to Sumatra. The basis for reporting the species from Pakistan, Myanmar or Bangladesh could not be located. Misidentified museum specimens from Myanmar and Pakistan identified as P. cupanus were never published on. Pseudosphromenus cupanus has been considered recently to be extinct in Bangladesh, but in fact it never occurred there.
Keywords: Asia, Freshwater, Geographical distribution, Threat status
Lancaster L, Dudaniec R, Hansson B, Svensson E (2015)
Latitudinal shift in thermal niche breadth results from thermal release during a climate-mediated range expansion
Journal of Biogeography 42(10).
Aim Climate change is currently altering the geographical distribution of species, but how this process contributes to biogeographical variation in ecological traits is unknown. Range-shifting species are predicted to encounter and respond to new selective regimes during their expansion phase, but also carry historical adaptations to their ancestral range. We sought to identify how historical and novel components of the environment interact to shape latitudinal trends in thermal tolerance, thermal tolerance breadth and phenotypic plasticity of a range-shifting species. Location Southern and central Sweden. Methods To evaluate phenotypic responses to changes in the thermal selective environment, we experimentally determined the upper and lower thermal tolerances of > 2000 wild-caught damselflies (Ischnura elegans) from populations distributed across core and expanding range-edge regions. We then identified changing correlations between thermal tolerance, climate and recent weather events across the range expansion. Niche modelling was employed to evaluate the relative contributions of varying climatic selective regimes to overall habitat suitability for the species in core versus range-edge regions. Results Upper thermal tolerance exhibited local adaptation to climate in the core region, but showed evidence of having been released from thermal selection during the current range expansion. In contrast, chill coma recovery exhibited local adaptation across the core region and range expansion, corresponding to increased climatic variability at higher latitudes. Adaptive plasticity of lower thermal tolerances (acclimation ability) increased towards the northern, expanding range edge. Main conclusions Our results suggest micro-evolutionary mechanisms for several large-scale and general biogeographical patterns, including spatially and latitudinally invariant heat tolerances (Brett's rule) and increased thermal acclimation rates and niche breadths at higher latitudes. Population-level processes unique to climate-mediated range expansions may commonly underpin many broader, macro-physiological trends.
Keywords: Character release, Ischnura elegans, Maxent, Sweden, colonization and range shifts, habitat suitability, insect invasions, macroecology, species distribution model, thermotolerance