Unusual abundance–range size relationship in an Afromontane bird community: the effect of geographical isolation?

Aim To show that the frequently reported positive trend in the abundance–range‐size relationship does not hold true within a montane bird community of Afrotropical highlands; to test possible explanations of the extraordinary shape of this relationship; and to discuss the influence of island effects on patterns of bird abundance in the Cameroon Mountains. Location Bamenda Highlands, Cameroon, Western Africa. Methods We censused birds during the breeding season in November and December 2003 using a point‐count method and mapped habitat structure at these census points. Local habitat requirements of each species detected by point counts were quantified using canonical correspondence analysis, and the size of geographical ranges of species was measured from their distribution maps for sub‐Saharan Africa. We tested differences in abundance, niche breadth and niche position between three species groups: endemic bird species of the Cameroon Mountains, non‐endemic Afromontane species, and widespread species. Results We detected neither a positive nor negative abundance–range‐size relationship in the bird community studied. This pattern was caused by the similar abundance of widespread, endemic and non‐endemic montane bird species. Moreover, endemic and non‐endemic montane species had broader local niches than widespread species. The widespread species also used more atypical habitats, as indicated by the slightly larger values of their niche positions. Main conclusions The relationship detected between abundance and range size does not correspond with that inferred from contemporary macroecological theory. We suggest that island effects are responsible for the observed pattern. Relatively high abundances of montane species are probably caused by their adaptation to local environmental conditions, which was enabled by climatic stability and the isolation of montane forest in the Cameroon Mountains. Such a unique environment provides a less suitable habitat for widespread species. Montane species, which are abundant at present, may also have had large ranges in glacial periods, but their post‐glacial distribution may have become restricted after the retreat of the montane forest. On the basis of comparison of our results with studies describing the abundance structure of bird communities in other montane areas in the Afrotropics, we suggest that the detected patterns may be universal throughout Afromontane forests.     

Ecological differentiation between the Sardinian endemic Maniola nurag and the pan-European M. jurtina

Recently refined evolutionary theories have highlighted that ecological interactions and environmental gradients can play a major role in speciation. This paper reports on a 3‐year field study, in which the ecology of two congeneric butterfly species was used to explore and compare the environmental factors determining their spatial distribution. These data are discussed in the context of possible speciation scenarios between the Sardinian populations of Maniola nurag and M. jurtina. M. nurag is endemic to the island of Sardinia, while M. jurtina is widespread over Europe. In Sardinia, the two species are locally sympatric. Mark–release–recapture experiments were combined with measures of environmental variables in 15 1‐ha plots, established in areas of potential habitat for the butterflies. Constrained linear models were parameterized from mark–recapture data to estimate both individual (survival and capture probabilities) and population (population size and recruitment) parameters. The two species had similar demography, movement patterns, life history, and behaviour. Population sizes developed in a parabolic fashion from beginning to end of the flight season. Differences included local population size, adult phenology, and habitat requirements. Long‐distance movements larger than 1.5 km were observed, suggesting a substantial amount of gene‐flow between populations of the endemic as well as the widespread species. Multivariate analyses revealed four main environmental gradients responsible for the abundance of the butterflies in an area. Both species responded similarly to environmental variables. However, each species’s abundance was correlated with a different environmental gradient determined by vegetation cover and structure. When sympatric, the two species responded to subtle differences in microhabitat structure. This might originally have induced their divergence. This study is an example of how empirical field data on population dynamics, dispersal, and habitat characteristics of two sympatric congeners can further our understanding of how species differentiate despite existing gene‐flow. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 89 , 561–574.     

Do rock endemic and widespread plant species differ under the Leaf–Height–Seed plant ecology strategy scheme?

Westoby (1998) proposed the Leaf–Height–Seed (L–H–S) scheme, i.e. the use of three functional traits, specific leaf area (SLA), plant canopy height and seed mass, to describe plant ecological strategies. In this study, we examine whether endemic species from cliffs and rocky outcrops can be discriminated in a regional Mediterranean flora according to these three traits. First, we conducted a comparison across 13 pairs of rock endemic species and widespread congeners. Second, we performed a canonical discriminant analysis to compare the position in the L–H–S volume of these 13 pairs of endemic and widespread congeners with that of 35 phylogenetically unrelated widespread species taken from the same regional flora. Our results show that rock endemic species only differ from their widespread congeners in their smaller stature. However, when compared with the 35 unrelated widespread species, endemic species are discriminated by higher SLA and taller stature, and thus are not close to the stress‐tolerant pole of ecological strategies (small stature, low SLA), as hypothesized in the literature.     

Does a ruderal strategy dominate the endemic flora of the West African forests?

Aim  To understand the distribution pattern of endemic plant species in West African rain forests, one of the global priority areas for biodiversity conservation.
Location  Upper Guinean forests, West Africa (Senegal, Guinea-Bissau, Guinea, Sierra Leone, Liberia, Côte d'Ivoire, Ghana and Togo).
Methods  We used herbarium collections from the whole Upper Guinean region ( sensu White 1981) to analyse the distribution patterns of 216 vascular plant species (approximately one-third of the endemic flora ranging from herbs to trees) that are restricted to these rain forests. We related species distribution ranges and species commonness to the main environmental variables and species life-history traits.
Results  We found that most endemic species of West African forests have large distribution ranges and ruderal strategies. Among all plant life-forms, species with small ranges were restricted to very moist places whereas more widespread species were less dependent on the availability of water. These more common species seem able to tolerate drier conditions, indicated by the minimum rainfall conditions where they are found and the positive correlation with local habitat openness. Light-demanding endemics were more common and widespread than shade-tolerant species, and there was a trend towards wind-dispersed species having a higher proportion of records in open places. This suggests that how widespread and common an endemic species is depends on being able to tolerate open and drier conditions.
Main conclusions  A ruderal strategy seems to be key for understanding the success of endemics in the Upper Guinean forests, and indicates the important role of disturbances in shaping the composition of these tropical forests. Our results have large implications for predicting the potential effect of increasing drought on rare endemic plant species of West African forests.     

Invasibility and species richness of island endemic arthropods: a general model of endemic vs. exotic species

Aim This paper has two objectives. First, we examine how a variety of biotic, abiotic and anthropogenic factors influence the endemic and introduced arthropod richness on an oceanic island. Second, we look at the relationship between the endemic and introduced arthropod richness, to ask whether areas with high levels of endemic species richness deter invasions. Location The work was carried out on a young volcanic island, Terceira, in the Azores. Methods We used standard techniques to collect data on arthropod species richness. Environmental data were obtained from the CIELO climatic model and using GIS. The explanatory value of environmental variables on a small‐scale gradient of endemic and exotic arthropod species richness was examined with generalized linear models (GLMs). In addition, the impact of both endemic and exotic species richness in the communities was assessed by entering them after the environmental variable(s) to see if they contributed significantly to the final model (the hierarchical method). Results Abiotic (climatic and geomorphological) variables gave a better explanation of the variation in endemic species richness, whereas anthropogenic variables explained most of the variation in introduced species richness. Furthermore, after accounting for all environmental variables, part of the unexplained variance in the endemic species richness is explained by the introduced species richness and vice‐versa. That is, areas with high levels of endemic species richness had many introduced species. There is evidence of a somewhat inverse spatial distribution between a group of oceanic‐type, forest‐dwelling, endemic, relict arthropods and a group of more generalist endemic arthropods that are able to survive in disturbed marginal sites particularly rich in non‐indigenous species. Main conclusions Richness of endemic species is mainly driven by abiotic factors such as a climatic axis (oceanic‐type localities with lower temperatures and summer precipitations) and a binary variable CALD (location of sites in caldeiras or ravines), whereas richness of introduced species depends on disturbance related factors. However, after factoring out these major influences, there is a correlation between endemic and introduced richness, suggesting that – independent of the environmental and geographical factors that affect the distribution of endemic or introduced species – the richest endemic assemblages are more prone to invasion, due probably to a facilitation process. Inconclusive evidence suggests that non‐indigenous species are limited to those sites under anthropogenic influence located mainly near forest edges, but the rate of expansion of those species to high‐altitude, core pristine sites has still to be tested.     

Deconstructing the mammal species richness pattern in Europe – towards an understanding of the relative importance of climate,biogeographic history,habitat heterogeneity and humans

Aim We deconstructed the mammal species richness pattern in Europe to assess the importance of large‐scale gradients in current macroclimate relative to biogeographic history, habitat heterogeneity and human influence (HHH variables) as richness determinants for total species, and for widespread and endemic species separately. Location Europe, west of 30° E. Methods We deconstructed total species richness (50‐km resolution) into its widespread and endemic species richness components. We used simultaneous autoregressive modelling (SAR) with information‐theoretic model selection and variation partitioning to assess the importance of macroclimate and HHH variables. The HHH variables included two historical factors, estimated by novel methodologies: (1) ice‐age‐driven dynamics, represented by accessibility to recolonization from hindcasting‐estimated glacial refugia, and (2) biogeographic peninsular dynamics, represented by distance to the entry region for the main European faunal source in western Asia. Results A large fraction of explained variation was shared between macroclimate and HHH in the SAR models. For total species richness, more variation could be uniquely attributed to macroclimate than to HHH, whereas for the deconstructed patterns (widespread and endemic species) the opposite was the case. Considering the individual factors, there was a strong peninsula effect on both widespread and endemic species richness but not on total richness. Main conclusions Both macroclimate and HHH variables (history, habitat heterogeneity and human influence) proved important predictors of species richness, but also difficult to disentangle. Notably, biogeographic history, in particular peninsular dynamics, is an important determinant of widespread and endemic species richness.     

Rarity, commonness, and patterns of species richness: the mammals of Mexico

Aim To determine whether rare or common species contribute most to overall patterns of spatial variation in extant species richness. Location Mexico. Methods Using data on the distribution of mammal species across Mexico at a quarter degree resolution, we ranked species from the most widespread to the most restricted (common‐to‐rare) within the study area, and from the most restricted to the most widespread (rare‐to‐common), and generated a sequence of patterns of species richness for increasing numbers of species. At each stage along both series of richness patterns, we correlated the species richness pattern for the subassemblage with that of the full assemblage. This allows comparison of subassemblages of the n most common with the n most rare species, in terms of how well they match the full assemblage richness pattern. Further analyses examined the effects on these patterns of correlation of the amount of raw information contained in the distributions of given numbers of rare and common species. Results For the mammals of Mexico the more widely distributed species contribute disproportionately to patterns of species richness compared with more restricted species, particularly for non‐volant species and endemic species. This is not simply a consequence of differences in the volumes of information contained in the distributions of rare and common species, with the disproportionate contribution of common species if anything being sharpened when these differences are taken into account. The pattern is most clearly demonstrated by endemic species, suggesting that the contribution of common species is clearest when the causes of rarity and commonness are limited to those genuinely resulting in narrow and widespread geographical ranges, respectively, rather than artificial (e.g. geopolitical) boundaries to the extents of study regions. Conclusions Perhaps surprisingly, an understanding of the determinants of overall patterns of species richness may gain most from consideration of why common species occur in some areas and are absent from others, rather than consideration of the distributions of rare species.     

Taxonomic and functional homogenization of an endemic desert fish fauna

Aim The highly endemic fishes of the arid Southwest USA have been heavily impacted by human activities resulting in one of the most threatened fish faunas in the world. The aim of this study was to examine the patterns and drivers of taxonomic and functional beta diversity of freshwater fish in the Lower Colorado River Basin across the 20th century. Location Lower Colorado River Basin (LCRB). Methods The taxonomic and functional similarities of watersheds were quantified to identify patterns of biotic homogenization or differentiation over the period 1900–1999. Path analysis was used to identify the relative influence of dam density, urban land use, precipitation regimes and non‐native species richness on observed changes in fish faunal composition. Results The fish fauna of the LCRB has become increasingly homogenized, both taxonomically (1.1% based on β_sim index) and functionally (6.2% based on Bray–Curtis index), over the 20th century. The rate of homogenization varied substantially; range declines of native species initially caused taxonomic differentiation (?7.9% in the 1960s), followed by marginal homogenization (observed in the 1990s) in response to an influx of non‐native species introductions. By contrast, functional homogenization of the basin was evident considerably earlier (in the 1950s) because of the widespread introduction of non‐native species sharing similar suites of biological traits. Path analysis revealed that both taxonomic and functional homogenization were positively related to the direct and indirect (facilitation by dams and urbanization) effects of non‐native species richness. Main conclusions Our study simultaneously examines rates of change in multiple dimensions of the homogenization process. For the endemic fish fauna of the LCRB, we found that the processes of taxonomic and functional homogenization are highly dynamic over time, varying both in terms of the magnitude and rate of change over the 20th century.     

Modelling the geographic distributions of endemic genera in the eastern Central Asian desert

This study simulates the distributions of 13 endemic and near‐endemic genera (Ammopiptanthus, Sympegma, Iljinia, Elachanthemum, Potaninia, Tugarinovia, Kaschgaria, Sarcozygium, Timouria, Zollikoferia, Stilpnolepis, Synstemon and Tetraena) to indicate areas of plant diversity and conservation importance within the eastern Central Asian desert, and to identify the determinant environmental variables contributing to the spatial distribution patterns. Using known distribution localities and 14 environmental variables, the Maxent and Domain species distribution models were employed to map the patterns of geographic distribution. The power of predictability of the models was tested using the receiver operating characteristic method and the jackknife validation approach, according to the different number of species localities available. The estimated richness and the superimposed potential distributions of 13 genera were used to indicate endemic patterns of distribution. The comparison of Maxent and Domain further identified previously unknown areas of endemism and described the distribution for each taxon. Both observed species occurrence and the species occurrence predicted from the Maxent indicated that the eastern Alashan of Inner Mongolia is the most noticeable endemic area, and the northwestern and northern Tarim Basin of Xinjiang is the secondary center of plant diversity. These regions were then prioritized for conservation importance. Potential evapotranspiration ratio and precipitation seasonality played important roles in driving the observed patterns of endemic distribution.     

Diversity of warning signal and social interaction influences the evolution of imperfect mimicry

Mimicry, the resemblance of one species by another, is a complex phenomenon where the mimic (Batesian mimicry) or the model and the mimic (Mullerian mimicry) gain an advantage from this phenotypic convergence. Despite the expectation that mimics should closely resemble their models, many mimetic species appear to be poor mimics. This is particularly apparent in some systems in which there are multiple available models. However, the influence of model pattern diversity on the evolution of mimetic systems remains poorly understood. We tested whether the number of model patterns a predator learns to associate with a negative consequence affects their willingness to try imperfect, novel patterns. We exposed week‐old chickens to coral snake (Micrurus) color patterns representative of three South American areas that differ in model pattern richness, and then tested their response to the putative imperfect mimetic pattern of a widespread species of harmless colubrid snake (Oxyrhopus rhombifer) in different social contexts. Our results indicate that chicks have a great hesitation to attack when individually exposed to high model pattern diversity and a greater hesitation to attack when exposed as a group to low model pattern diversity. Individuals with a fast growth trajectory (measured by morphological traits) were also less reluctant to attack. We suggest that the evolution of new patterns could be favored by social learning in areas of low pattern diversity, while individual learning can reduce predation pressure on recently evolved mimics in areas of high model diversity. Our results could aid the development of ecological predictions about the evolution of imperfect mimicry and mimicry in general.     

Investigations in plant commonness and rarity: a comparison of seed removal patterns in the widespread Jatropha standleyi and the endemic J. chamelensis (Euphorbiaceae)

During early August to late September 1998 we examined seed dispersal in the tree species Jatropha standleyi (widespread) and J. chamelensis (endemic; Euphorbiaceae) at the Estacion de Biologia Chamela, Jalisco, Mexico. Using general linear models, we found that seed removal from beneath the parental canopy did not differ between the two species and that seed removal was correlated with both seed availability on the ground and rodent predation. We inferred that seed removal was largely mediated by rodents and determined that if a seed was not removed within 4d (approx. 16% chance), it was highly unlikely to be removed at all (approx. 3.5% chance) for both species. We note that although differences in patterns of seed removal may not explain the observed differences in range size, differences between the two species in seed crop size arc similar to patterns found in other endemic/widespread species pairs.     

Distribution of vascular plant species richness and endemic richness along the Himalayan elevation gradient in Nepal

Aim Species richness and endemic richness vary along elevation gradients, but not necessarily in the same way. This study tests if the maxima in gamma diversity for flowering plants and the endemic subset of these plants are coherent or not. Location The study was conducted in Nepal, between 1000 and 5000 m a.s.l. Methods We used published data on distribution and elevational ranges of the Nepalese flora to interpolate presence between maximum and minimum elevations. Correlation, regression and graphical analyses were used to evaluate the diversity pattern between 1000 and 5000 m a.s.l. Results The interval of maximum species endemic to Nepal or the Himalayas (3800–4200 m) is above the interval of maximum richness (1500–2500 m). The exact location of maximum species density is uncertain and its accuracy depends on ecologically sound estimates of area in the elevation zones. There is no positive statistically significant correlation between log‐area and richness (total or endemic). Total richness is positively correlated with log‐area‐adjusted, i.e. estimated area adjusted for the degree of topographic heterogeneity. The proportion of endemic species increases steadily from low to high elevations. The peak in endemism (c. 4000 m) corresponds to the start of a rapid decrease in species richness above 4000 m. This may relate to the last glacial maximum (equilibrium line at c. 4000 m) that penetrated down to 2500–3000 m. This dynamic hard boundary may have caused an increase in the extinction rate above 4000 m, and enhanced the probability of isolation and facilitated speciation of neoendemics, especially among genera with a high proportion of polyploids. Main conclusions The results reject the idea of corresponding maxima in endemic species and species richness in the lowlands tentatively deduced from Stevens’ elevational Rapoport effect. They confirm predictions based on hard boundary theory, but hard‐boundaries should be viewed as dynamic rather than static when broad‐scale biogeographical patterns with a historical component are being interpreted.     

Population genomic response to geographic gradients by widespread and endemic fishes of the Arabian Peninsula

Genetic structure within marine species may be driven by local adaptation to their environment, or alternatively by historical processes, such as geographic isolation. The gulfs and seas bordering the Arabian Peninsula offer an ideal setting to examine connectivity patterns in coral reef fishes with respect to environmental gradients and vicariance. The Red Sea is characterized by a unique marine fauna, historical periods of desiccation and isolation, as well as environmental gradients in salinity, temperature, and primary productivity that vary both by latitude and by season. The adjacent Arabian Sea is characterized by a sharper environmental gradient, ranging from extensive coral cover and warm temperatures in the southwest, to sparse coral cover, cooler temperatures, and seasonal upwelling in the northeast. Reef fish, however, are not confined to these seas, with some Red Sea fishes extending varying distances into the northern Arabian Sea, while their pelagic larvae are presumably capable of much greater dispersal. These species must therefore cope with a diversity of conditions that invoke the possibility of steep clines in natural selection. Here, we test for genetic structure in two widespread reef fish species (a butterflyfish and surgeonfish) and eight range‐restricted butterflyfishes across the Red Sea and Arabian Sea using genome‐wide single nucleotide polymorphisms. We performed multiple matrix regression with randomization analyses on genetic distances for all species, as well as reconstructed scenarios for population subdivision in the species with signatures of isolation. We found that (a) widespread species displayed more genetic subdivision than regional endemics and (b) this genetic structure was not correlated with contemporary environmental parameters but instead may reflect historical events. We propose that the endemic species may be adapted to a diversity of local conditions, but the widespread species are instead subject to ecological filtering where different combinations of genotypes persist under divergent ecological regimes.     

The biology and ecology of narrow endemic and widespread plants: a comparative study of trait variation in 20 congeneric pairs

The objective of this study is to examine whether habitat, herbivory and traits related to resource acquisition, resource conservation, reproduction and dispersal differ between narrow endemic plant species and their widespread congeners. We undertook pairwise contrasts of 25 ecological characteristics and biological traits in 20 congeneric pairs of narrow endemic and widespread plant species in the French Mediterranean region. Within each pair, the two species had the same life-form, pollination mode and dispersal mode. Endemic species differed significantly from widespread congeners for a number of attributes. Endemic species occur in habitats on steeper slopes, with higher rock cover and in lower and more open vegetation than their widespread congeners. Endemic species are significantly smaller than widespread species, but show no differences in traits related to resource acquisition (specific leaf area, leaf nitrogen content, maximum photosynthetic rate) or resource conservation (leaf dry matter content). After accounting for their smaller stature, endemic species produce fewer and smaller flowers with less stigma-anther separation and lower pollen/ovule ratios and produce fewer seeds per plant than their widespread congeners. No consistent variation in seed mass and propagule structure was found between congeneric species. Herbivory levels did not differ between congeneric species. Ecological characteristics, notably the occupation of rocky habitats with low aboveground competition, may thus have played an important role in the differentiation of narrow endemic species in the Western Mediterranean. Morphological and ecophysiological traits of narrow endemic species indicate that they are not more stress-tolerant than their widespread congeners. Lower investment in pollen transfer and seed production suggest that local persistence is a key feature of the population ecology of narrow endemic species.     

Ingestion by an endemic frugivore enhances seed germination of endemic plant species but decreases seedling survival of exotics

Aim To test whether ingestion by endemic frugivores differentially affects the seed germination time, germination percentage and seedling survival of endemic, native and exotic fleshy fruited plant species, and to identify the principal processes and attributes driving such effects. Location Round Island, Mauritius. Methods We conducted a germination and seedling survival experiment for 3 months to test whether ingestion (gut passage and deposition in faeces) by the endemic Telfair’s skink (Leiolopisma telfairii) had a differential effect on the germination time, germination percentage and seedling survival of two endemic, four native and two exotic fleshy fruited plant species. To assess the importance of factors involved in the ingestion process, we used a factorial design with gut passage (gut‐passed vs. not gut‐passed), depulping (whole fruit vs. manually depulped seed) and the presence of faecal material (faeces vs. without faeces). In addition, the roles of species‐specific traits, seed size and deposition density (average number of seeds per faeces) were examined. Results Exotic species had a higher germination percentage than indigenous (native and endemic) species when not ingested. Following skink ingestion, there was no longer a difference, as ingestion enhanced germination percentage most in endemic species. The exotic species still germinated faster overall than the indigenous species, despite ingestion accelerating the germination time of endemics. However, ingestion strongly reduced seedling survival of the exotic species, while having no negative effect on the survival of indigenous seedlings. Overall, ingested indigenous seeds were more likely to germinate and the seedlings more likely to survive than ingested exotic seeds and seedlings. Seed size, deposition density and the removal of fruit pulp by either manual depulping or gut passage were important predictors of germination time, germination percentage and seedling survival. Main conclusions These endemic frugivores can enhance the competitiveness of endemic compared with exotic fleshy fruited plants at the critical germination and seedling establishment stage. Consequently, conservation and restoration of mutualistic endemic plant–animal interactions may be vital to mitigating the degradation of habitats invaded by exotic plants, which is of particular relevance for island ecosystems in which large numbers of endemics are threatened by exotic invaders.     

Filling the gap: Length–weight and length–length relationships of intertidal endemic fishes of the Brazilian Province Oceanic Islands

Length‐weight and length‐length relationships were determined for nine fish species of Rocas Atoll, Fernando de Noronha and Trindade Island. Samples were conducted in 2014 (Rocas) and 2015 (Noronha and Trindade) in tidepools using anaesthetic clove oil and hand nets to collect fish fauna. Four species (Stegastes rocasensis, Scartella itajobi, Starksia multilepis and Bathygobius brasiliensis) are endemic from the Noronha‐Rocas ridge, two are endemic from the Trindade‐Martin Vaz insular complex (Scartella poiti and Malacoctenus brunoi), and three species have a widespread distribution. All relationships are novel for science.     

河南省特有种植物区系地理研究

首次对河南省特有种及其区系地理和生态学特点进行了研究。结果显示:(1)河南特有植物有42种,隶属于37属,25科;(2)草本植物占64%,与河南维管植物区系的草本比例基本相同,其中多数为多年生草本,特有种绝大多数为陆生中生植物;(3)根据它们的分布特点,特有种可分为6个分布型,其中属于豫西山地分布型的种类最多,占总种数的60%;(4)这些特有种集中分布于豫西、豫南、豫西北山地和豫中黄河两岸四个地区,种类最多的是豫西山地。     

Phylogenetics of Darwiniothamnus (Asteraceae: Astereae) – molecular evidence for multiple origins in the endemic flora of the Galápagos Islands

Aim The aims of this study were (1) to investigate whether the two growth forms of Darwiniothamnus Harling (Asteraceae) originated from the colonization of a single ancestor, (2) to identify the closest relative(s) of Darwiniothamnus, and (3) to review molecular phylogenies from other plant groups to infer the origin of Galápagos endemics. Location Darwiniothamnus is endemic to the Galápagos Islands. Methods All putative relatives of Darwiniothamnus plus 38 additional species were included. Nucleotide sequences of the internal transcribed spacers of the nuclear ribosomal DNA were used for Bayesian and parsimony analyses. Results Darwiniothamnus is polyphyletic. Two species (D. lancifolius (Hook. f.) Harling and D. tenuifolius (Hook. f.) Harling) are woody shrubs that usually grow to 1–2 m in height; they belong to a clade composed of species otherwise restricted to the Caribbean. These two species are sister to Erigeron bellidiastroides Griseb., a herbaceous species endemic to Cuba. The third species (D. alternifolius Lawesson & Adsersen) is a perennial herbaceous plant, woody at the base and reaching only up to 50 cm in height. It is sister to two Chilean (Coquimbo–Valparaiso region) species that also have a perennial herbaceous habit: E. fasciculatus Colla and E. luxurians (Skottsb.) Solbrig. They are placed in an assemblage restricted to South America. The review of previous molecular phylogenetic studies revealed that two of the endemic genera and endemic species of three non‐endemic genera have their closest relatives in South America. Endemic species belonging to three non‐endemic genera have sister species in North America or the West Indies. One endemic genus and endemic species in three non‐endemic genera have sister taxa with a widespread continental distribution, or their molecular phylogenies yielded equivocal results. Main conclusions The flora of Galápagos has affinities with both North America (including the Antilles) and South America. Darwiniothamnus exhibits both patterns: two species of this genus are sister to a taxon endemic to Cuba, supporting a connection between the Cocos plate and the West Indies; the third species, D. alternifolius, provides a link with the Coquimbo–Valparaiso region, suggesting a biogeographical connection between the Nazca plate and southern South America.     

Coping with Pleistocene climatic fluctuations: Demographic responses in remote endemic reef fishes

Elucidating demographic history during the settlement of ecological communities is crucial for properly inferring the mechanisms that shape patterns of species diversity and their persistence through time. Here, we used genomic data and coalescent‐based approaches to elucidate for the first time the demographic dynamics associated with the settlement by endemic reef fish fauna of one of the most remote peripheral islands of the Pacific Ocean, Rapa Nui (Easter Island). We compared the demographic history of nine endemic species in order to explore their demographic responses to Pleistocene climatic fluctuations. We found that species endemic to Rapa Nui share a common demographic history, as signatures of population expansions were retrieved for almost all of the species studied here, and synchronous demographic expansions initiated during the last glacial period were recovered for more than half of the studied species. These results suggest that eustatic fluctuations associated with Milankovitch cycles have played a central role in species demographic histories and in the final stage of the community assembly of many Rapa Nui reef fishes. Specifically, sea level lowstands resulted in the maximum reef habitat extension for Rapa Nui endemic species; we discuss the potential role of seamounts in allowing endemic species to cope with Pleistocene climatic fluctuations, and we highlight the importance of local historical processes over regional ones. Overall, our results shed light on the mechanisms by which endemism arises and is maintained in peripheral reef fish fauna.     

Current and historical factors influencing patterns of species richness and turnover of birds in the Gulf of Guinea highlands

Aim The aims of this paper are to: examine how current and historical ecological factors affect patterns of species richness, endemism and turnover in the Gulf of Guinea highlands, test theoretical biogeographical predictions and provide information for making informed conservation decisions. Location The Gulf of Guinea highlands in West Africa. Methods We used multivariate and matrix regression models, and cluster analyses to assess the influence of current climate and current and historical isolation on patterns of richness and turnover for montane birds across the highlands. We examined three groups of birds: montane species (including widespread species), montane endemics and endemic subspecies. We applied a complementarity‐based reserve selection algorithm using species richness with irreplaceability measures to identify areas of high conservation concern. Results Environmental factors influenced richness for all groups of birds (species, endemic species and subspecies). Areas with high and consistent annual rainfall showed the highest species and endemic richness. Species clusters for all groups of birds generally differentiated three major montane regions, which are topographically isolated. Multiple mantel tests identified these same regions for endemic species and subspecies. The influence of historical isolation varied by species group; distributions of endemic montane species and subspecies were more associated with historical breaks than were all montane species, which included widespread non‐endemic species. Main conclusions Our analyses indicated important geographical structure amongst the bird assemblages in the highlands and, therefore, conservation prioritization should include mountains from within the geographical subregions identified in these analyses because these regions may harbour evolutionarily distinct populations of birds.