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The southernmost portion of the Andes in South America hosts Nothofagaceae forests that form ectomycorrhizal (EcM) associations. We compiled all the published reports of EcM taxa from these woodlands, based on fruit-body collections and molecularly identified root tips. This resulted in 87 peer-reviewed research papers dealing with EcM associations from Nothofagaceae forests published over the past 62 years. Based on these papers the EcM richness and its association with Nothofagaceae species was analyzed. Represented by 45 genera (34 Basidiomycetes and 11 Ascomycetes), 479 EcM taxa have been recorded, plus an additional 46 EcM taxa which are potentially EcM. Cortinarius was the most frequent and diverse genus , with 64.9% of total species. Nothofagus dombeyi had the highest number of unique EcM species, followed by N. pumilio , N. antarctica and Lophozonia obliqua. The EcM community associated with Nothofagus species , except N. nitida, showed higher similarities among themselves, than with Lophozonia and Fuscospora species. Beta diversity indexes showed EcM Nothofagus species have 29–42% niche overlap, while Nothofagus — Lophozonia only had 1–16%. The assessment of the accuracy of the EcM diversity, host specificity and community structure deserve further studies combining phylogenetic analysis based on broad ecological surveys. On the basis of pre-selected criteria Austropaxillus statuum, Cortinarius fragilis, Cortinarius xiphidipus and Hallingea purpurea are proposed as candidates for nursery spore inoculations, and should be subject to scientific evaluation to determine costs and benefits. [ABSTRACT FROM AUTHOR]

The late Miocene and younger mafic back-arc lavas in the southern Puna of the central Andean plateau have been attributed to the aftermath of crustal and mantle lithospheric delamination or foundering. In this paper, we analyze in more detail the nature of the back-arc mafic suite magmas, including the conditions of magma generation in the mantle and of magma evolution during ascent and ponding in the crust, using extensive compositional data for phenocryst minerals and olivine-hosted melt inclusions in combination with published and new whole-rock chemical and isotopic data. We estimate that the primary melts last equilibrated with an enriched mantle source at temperatures near 1375°C and pressures near 2 GPa, which is near the base of the seismically determined ∼60 km thick crust. A mantle source geochemically enriched by continental material introduced through delamination and subducted erosion processes is required to explain the coincidence of the high 87Sr/86Sr ratios (>0·705) and high Sr concentrations (>700 ppm) of the most primitive lavas (e.g. 9–10 wt % MgO, olivine Fo88). The crystallization conditions inferred from mineral–melt equilibria indicate that olivine (T = 1320–1220°C) was followed by clinopyroxene (T = 1230–1140°C). Clinopyroxene–melt equilibration pressures of 0·7 to near 1 GPa in the most mafic samples indicate that the magmas crystallized at mid-crustal depths of 20–35 km, within a region of inferred partial melt accumulation based on the presence of low seismic velocity zones. Olivine-hosted melt inclusions indicate relatively dry melts (maximum 0·5 wt % H2O) with unusual high-Al basaltic compositions, which are attributed to the high-pressure suppression of plagioclase crystallization. A first stage of crustal contamination before mid-crustal accumulation and crystallization of the mafic magmas is suggested by high O-isotope ratios in olivine phenocrysts and negative Eu anomalies in clinopyroxene from the plagioclase-free mafic lavas. Mixing models based on trace elements and radiogenic isotopes suggest assimilation of silicic melt in the lower crust, similar to contemporaneous glassy dacites with steep REE patterns and negative Eu anomalies. A second stage of crustal assimilation at shallower depths is indicated by the mismatch of incompatible elements in clinopyroxene relative to bulk-rock compositions, by strong positive correlations of radiogenic isotopes with wt % SiO2, and by petrographic observation of partly resorbed and reacted quartz xenocrysts. Mixing calculations require the erupted magmas to have assimilated in total some 15–25% crust. [ABSTRACT FROM AUTHOR]

Background and Aims Studies examining patterns and processes of speciation in South America are fewer than in North America and Europe. One of the least well documented processes has been progenitor–derivative speciation. A particularly instructive example occurs in the southern Andes in the genus Pozoa (Apiaceae, Azorelloideae), which consists of only two diploid outcrossing species, the widespread P. coriacea and the geographically and ecologically restricted P. volcanica. This paper tests the hypothesis that the latter species originated from the former through local geographical and ecological isolation by progenitor–derivative speciation. Methods DNA sequences were analysed from Pozoa and the related South American genera Asteriscium, Eremocharis and Gymnophyton from non-coding regions of the plastid genome, ndhF-rpl32 and rpl32-trnL, plus incorporation of previously reported rpl16 intron and trnD-trnT intergenic spacer sequences. Amplified fragment length polymorphism (AFLP) data from 105 individuals in 21 populations throughout the entire range of distribution of the genus were used for estimation of genetic diversity, divergence and SplitsTree network analysis. Ecological factors, including habitat and associated species, were also examined. Key Results Pozoa coriacea is more similar genetically to the outgroup genera, Asteriscium and Eremocharis, than is P. volcanica. At the population level, only P. volcanica is monophyletic, whereas P. coriacea is paraphyletic. Analyses of genetic differentiation among populations and genetic divergence and diversity of the species show highest values in P. coriacea and clear reductions in P. volcanica. Pozoa coriacea occurs in several types of high elevation habitats, whereas P. volcanica is found only in newly formed open volcanic ash zones. Conclusions All facts support that Pozoa represents a good example of progenitor–derivative speciation in the Andes of southern South America. [ABSTRACT FROM PUBLISHER]

During the seventeenth and eighteenth centuries, Indigenous northern Andeans created intricate images to decorate wooden objects using a unique resin known as barniz de Pasto or mopa mopa. One of the pigments that they used is a mercury‐based substance called calomel. Before calomel was found in 2018 on a mopa mopa object, neither conservators nor art historians had ever known of the use of calomel as a pigment. In this essay I argue that calomel's use as white pigment in mopa mopa objects resulted from the encounter between two subaltern knowledge traditions rarely studied together: that of European women and Indigenous Andeans. Through an object‐based approach, I trace the knowledge and expertise required to handle materials like calomel and mopa mopa resin, highlighting the essential role of objects in recovering the vernacular paths of knowledge that contributed to the transformation of the early modern world. [ABSTRACT FROM AUTHOR]

Pike cichlids form the largest clade of Neotropical cichlids, with over 100 species presently classified in two genera: Crenicichla (93 species widespread in rivers of South America east of the Andes) and Teleocichla (nine rheophilic Amazonian species). Here, we combined a new dataset of 216 morphological characters with molecular data compiled from published sources, comprising 74 terminal taxa of pike cichlids (68 out of 102 valid species, plus four putative new species), and performed phylogenetic analyses using maximum likelihood, Bayesian inference, and parsimony. Based on a synthesis of our results and previous phylogenies, we propose a new classification in which the clade including all pike cichlids is elevated to the rank of subtribe (Crenicichlina) and the genus Crenicichla is redefined, including three subgenera: Crenicichla (monotypic with the type species), Batrachops (resurected as subgenus), and Lacustria (new subgenus). Teleocichla is maintained as a valid genus and four new genera are proposed: Wallaciia, Saxatilia, Hemeraia , and Lugubria. Our results on character mapping support the hypothesis that resource partitioning in environments with fast-flowing water and rocky beds might have played a role in the origin or maintenance of the great diversity of pike cichlids, resulting in parallel evolution of similar ecomorphs. [ABSTRACT FROM AUTHOR]

Background and Aims Understanding diaspore morphology and how much a species invests on dispersal appendages is key for improving our knowledge of dispersal in fragmented habitats. We investigate diaspore morphological traits in high-Andean Compositae and their main abiotic and biotic drivers and test whether they play a role in species distribution patterns across the naturally fragmented high-Andean grasslands. Methods We collected diaspore trait data for 125 Compositae species across 47 tropical high-Andean summits, focusing on achene length and pappus-to-achene length ratio, with the latter as a proxy of dispersal investment. We analysed the role of abiotic (temperature, elevation and latitude) and biotic factors (phylogenetic signal and differences between tribes) on diaspore traits and whether they are related to distribution patterns across the Andes, using phylogenomics, distribution modelling and community ecology analyses. Key Results Seventy-five percent of the studied species show small achenes (length <3.3 mm) and 67% have high dispersal investment (pappus length at least two times the achene length). Dispersal investment increases with elevation, possibly to compensate for lower air density, and achene length increases towards the equator, where non-seasonal climate prevails. Diaspore traits show significant phylogenetic signal, and higher dispersal investment is observed in Gnaphalieae, Astereae and Senecioneae, which together represent 72% of our species. High-Andean-restricted species found across the tropical Andes have, on average, the pappus four times longer than the achene, a significantly higher dispersal investment than species present only in the northern Andes or only in the central Andes. Conclusions Small achenes and high diaspore dispersal investment dominate among high-Andean Compositae, traits typical of mostly three tribes of African origin; but traits are also correlated with the environmental gradients within the high-Andean grasslands. Our results also suggest that diaspore dispersal investment is likely to shape species distribution patterns in naturally fragmented habitats. [ABSTRACT FROM AUTHOR]

The interplay among evolutionary mechanisms like gene flow and selection may result in discordant signals between mitochondrial DNA, nuclear markers and phenotypes. The Andean hummingbirds Coeligena bonapartei and Coeligena helianthea showed differentiation in the gene ND2 which is discordant with plumage coloration but consistent with geography. We analysed complete mitochondrial genomes of individuals from Coeligena bonapartei bonapartei , Coeligena bonapartei consita , Coeligena helianthea helianthea , and Coeligena helianthea tamai to inform their evolutionary history. We found genetic structure despite low genetic differentiation among these populations. Phylogenetic and network analyses based on mitogenomes showed a northern vs. southern differentiation pattern which is discordant with the relationships based on nuclear markers and the coloration phenotypes (serving as a basis for taxonomy). Mitogenomes of the two nominate subspecies are indistinguishable, suggesting incomplete lineage sorting or introgression, while those of C. b. consita and C. h. tamai are more similar to each other than they are to their respective nominate subspecies. Our results indicate that various evolutionary mechanisms drove the divergence in phenotypes, and nuclear and mitochondrial genomes of Coeligena hummingbirds, playing out over a complex biogeographic scenario likely involving periods of isolation and secondary contact. We outline hypotheses to be tested with future analyses of genome-wide variation. [ABSTRACT FROM AUTHOR]

Osorno volcano (41°06'S, 72°20'W) is a composite stratovolcano of the Central Southern Volcanic Zone of the Chilean Andes. It is the southernmost member of a NE–SW trending alignment of volcanic edifices including La Picada and Puntiagudo volcanoes and the Cordón Cenizos chain. According to contemporary descriptions recorded by Charles Darwin in 1835, two eruptive events occurred: the first during January–February, and the second during November–December 1835 and January 1836. The volcano erupted basaltic andesite lavas and tephra fall deposits (52.4 to 52.9 SiO2 wt. %), which contain phenocrysts of olivine, plagioclase, clinopyroxene, and spinel. The compositions of these phenocryst phases, together with those of olivine-hosted melt inclusions, allowed us to constrain intensive parameters for the pre-eruptive magmas. These varied from 1060°C to 1140°C, with an oxygen fugacity buffer of ~ΔQFM +1.1, dissolved water concentrations of up to 5.6 wt. % (average of ~4.2 wt. %) and maximum pressures equivalent to ~7-km depth. Textural relations, such as crystal accumulations and clots, zoning in crystals and other indications of disequilibrium, lead us to infer the involvement of a crystal mush, rich in individual crystals and clots of crystals, which underwent a degree of disaggregation and entrainment into the transiting magma prior to eruption. Comparison of trace element abundances, including rare earth elements, fluid-mobile elements, and relatively fluid-immobile elements, combined with 87Sr/86Sr and 143Nd/144Nd isotope ratios, allows us to consider variations in slab-derived fluid input and the minor role of crustal contamination on the Osorno eruptive products and those from neighboring volcanic systems. Our results suggest both a greater contribution from slab-derived fluid and a higher degree of partial melting in the systems supplying stratovolcanoes (Osorno, Calbuco, and La Picada) relative to those supplying small eruptive centers built over the major regional Liquiñe-Ofqui Fault Zone. [ABSTRACT FROM AUTHOR]

The Andean region is one of the most biodiverse areas, displaying high levels of endemism and spatial turnover of species. Tribe Eudemeae includes nine genera and 40 species distributed from the northern Andes in Colombia to the southernmost portion of the Andes in Argentina and Chile. Here, we generated a species-level phylogenetic tree to study their climatic niche evolution. We first analysed phylogenetic structure and evolutionary shifts among the main climatic spaces using model-based estimates. Second, we estimated climatic niches for each species and compared them in a phylogenetic context. In Eudemeae, three main groups of climatic spaces were found, mainly related to the northern and central Andes, the north-central portion of the southern Andes and the central-southern portion of the southern Andes. Results suggest that initial colonization of new climatic spaces in the evolution of the tribe appears to be promoted through shifts in adaptive regimes, whereas subsequent diversification of genera occurred predominantly under the same climatic regimes. This trade-off between niche conservatism and divergence appears to have modulated their diversification across the Andes and contributed to their current geographical distribution. [ABSTRACT FROM AUTHOR]

A "service provision" value chain that sustains the activities of the Las Bambas copper mine cuts across rural communities and the mining town, connected by the invisibilized work of indigenous and/or migrant women, through their maintenance of the rural homestead, or in their provision of feminized services, essential to men who work in the urban center near the mine. We argue that in this case women's access to mining's benefits and/or jobs in both rural and urban spaces is mediated by gender, as mining's direct and indirect effects serve to consolidate their social reproductive roles. [ABSTRACT FROM AUTHOR]

The complex Moho topography beneath the northwestern Andes is the result of multiple geodynamic processes during the Cenozoic. To contribute to our understanding of the Moho depth distribution beneath this region, we inverted gravity data from two widely used satellite-derived data sets (EGM2008 and EIGEN-6C4) and one regional airborne Bouguer gravity anomaly map (ANH2010). Their inversion allowed choosing the ANH2010, based on lower residual gravity and a higher agreement with seismic estimations, as the most suitable data set to gain insights into the Moho depth beneath the northwestern Andes and its relationship with previously identified tectonic features. The inverted Moho argues for a 40–50 km depth beneath the Central and Eastern cordilleras, reaching depths beyond 50 km below the Eastern Cordillera, and shallower depths between 30 and 40 km mainly along the foreland region to the east, the Western Cordillera and the coastal plains. Three main thickened crust features of regional extent were identified: (1) a deep Moho expression with a crustal thickness greater than 40 km in the northwesternmost foreland region, which we consider a direct consequence of the adjacent thickened Eastern Cordillera involving the fold and thrust deformation migration from the range towards the foreland, and the flexural deformation proposed for the eastern foothills; (2) a regional deep Moho expression (50–60 km) along the axis of the Eastern Cordillera, related to its shortening history including multiple phases of Cenozoic thick-skinned deformation and magmatic underplating; and (3) a Moho deeper than 60 km in a southern latitude (1°S–1°N) beneath the modern magmatic arc, whose interpretation is more complex, likely a combined result of mafic addition to the base of the crust, foundering tectonics, and lateral displacement of the lower crust prompted by the subducting Carnegie ridge. [ABSTRACT FROM AUTHOR]

Species richness in the genus Pristimantis is underestimated due to the existence of morphologically cryptic species. This is worsened by the low sampling effort and the lack of studies using genetic markers. Here, we use molecular and morphological data to determine the phylogenetic relationships of a clade of Pristimantis distributed throughout montane tropical forests in the eastern Andes, from central Ecuador to northern Perú. We name this clade the Pristimantis trachyblepharis species group. Our results show that it comprises nine species, of which four are formally described and five are new. Four of these undescribed species are formally described here. The group is composed of miniaturized species, such as Pristimantis nanus sp. nov. , currently the smallest known species of the genus and the smallest vertebrate in Ecuador. As a first approach to understanding the evolutionary origin and implications of body-size reduction in Pristimantis , we here study the phylogenetic signal and evolutionary trends of body size within the genus. We also provide the first record of P. aquilonaris in Ecuador and we show, for the first time, the phylogenetic position of P. albujai , P. aquilonaris , P. minimus and P. trachyblepharis , which are also members of the P. trachyblepharis species group. [ABSTRACT FROM AUTHOR]

Hybridization can facilitate both evolutionary diversification and extinction and has had a critical role in plant evolution, with c. 25% of species known to hybridize in some temperate floras. However, in the species-rich Neotropical flora, the role of hybridization in the evolution of diversity remains unclear. Our review examines studies of hybridization in seed plants from across the Neotropics and explores its outcomes on Neotropical plant evolution. We review studies on a per-biome basis and a spectrum of evolutionary outcomes from hybridization are evident across Neotropical biomes and taxa. These range from short-term impacts, such as the broadening of ecological amplitude in hybrid progeny with transgressive phenotypes and genetic swamping, through to long term impacts, such as the generation of new lineages. Among these studies certain themes emerge, such as the pervasive hybridization among species-rich plant radiations from the Andean páramos, suggesting a role for hybridization in rapid diversification events. Finally, we highlight that hybridization is relatively understudied in the Neotropical flora, despite its remarkable species richness. The advent of genomic techniques can facilitate the study of hybridization and its effects in understudied biomes and plant groups. The increasing availability of genomic resources will eventually allow comparisons between tropical and temperate floras and therefore shed light on the evolutionary impacts of hybridization across the latitudinal biodiversity gradient. [ABSTRACT FROM AUTHOR]

Calceolaria (Calceolariaceae) is an emblematic and diverse genus in the Americas. Despite being one of the most easily recognized genera in the region and a system with great potential to improve our understanding of different drivers of species diversification in the Andes, its intrageneric evolutionary relationships are still poorly understood. Responding to the need for additional molecular markers to resolve the phylogenetic relationships of the group, we perform plastome analyses and resolve the backbone of the genus. Specifically, using low-coverage genomes for 14 species, we assembled plastomes, estimated and dated phylogenetic hypotheses and evaluated evolutionary trends in the group. Our approach allowed us to resolve the backbone of the genus, identify two main clades and estimate a timing of diversification contemporaneous to major climatic and orogenic events. Our biogeographic reconstructions suggest an independent colonization of the whole range of the genus by both clades. Finally, our evaluations of floral morphology reveal future avenues for investigating the relationship between the pollination biology and diversification of the group. [ABSTRACT FROM AUTHOR]

The humid mid-elevation montane forests (MMF) of the tropical Andes harbour high levels of plant species diversity, contributing to the exceptional overall diversity of the tropical Andean biodiversity hotspot. However, little is known about the diversification dynamics of MMF plant lineages compared to lineages in other Andean biomes. Here, we use Macrocarpaea (Gentianaceae) to investigate patterns of plant diversification in the MMF, using molecular dating with fossils and secondary calibration (from a family-wide phylogenetic analysis of Gentianaceae). We sequenced 76 of 118 recognized Macrocarpaea spp. for six markers to reconstruct a time-calibrated phylogenetic tree and infer the historical biogeography of Macrocarpaea using maximum-likelihood methods implemented in BioGeoBEARS, estimating diversification rates through time and among lineages with BAMM. We document a rapid radiation of Macrocarpaea in Andean MMF coinciding with rapid colonization and range expansion across the entire distribution of the genus in the Andes starting 7.2 Mya. Our results support allopatric founder-event speciation as the dominant process contributing to geographical phylogenetic structure across the genus. We propose that establishment of the MMF in the late Miocene, when the Andes attained critical elevation to modify regional climates, provided large new areas of suitable habitat for Macrocarpaea to quickly colonize and expand through repeated founder-events. We suggest that this wave of colonization and range expansion triggered rapid diversification, and, as the MMF became progressively occupied, the diversification rate slowed. Our study also supports the idea that MMF plant radiations are older and more slowly evolving than the quickly evolving lineages in the recent Andean high-elevation grasslands. [ABSTRACT FROM AUTHOR]

We investigated the land snail fauna along an altitudinal transect in the Los Cedros Biological Reserve on the western slope of the Andes in Ecuador. A total of 510 individuals were collected in 40 plots between c. 1,100 and 2,000 m a.s.l. and assigned to 80 land snail species. The mean iChao1 estimate of species richness was with 109 species (with a 95% confidence interval from 97 to 130 species) much higher because many species were represented only by one or two specimens. On the basis of available data, Los Cedros is the most species-rich locality for land snails in South America. Almost half of the land snail species and 75% of the sampled individuals belong to the carnivorous Scolodontidae, most of which are likely to be new to science. In comparison with an Amazonian rainforest, the proportion of tropical groups such as the Helicinoidea or the Achatinidae is reduced, whereas the proportions of the Labyrinthidae and Charopidae are higher at higher elevations in the Andes than at the margin of the Amazonas basin. Beckianum beckianum, Hirtudiscus sp. Pupisoma mediamericanum, Guppya gundlachii, Eobania vermiculata and Thysanophora plagioptycha are new records for Ecuador. The finding of the Mediterranean Eobania vermiculata in cultivated areas adjacent to the reserve is the first record of this species in South America. [ABSTRACT FROM AUTHOR]

Tropical pollinators are expected to experience substantial effects due to climate change, but aspects of their thermal biology remain largely unknown. We investigated the thermal tolerance of stingless honey-making bees, the most ecologically, economically and culturally important group of tropical pollinators. We assessed changes in the lower (CTMin) and upper (CTMax) critical thermal limits of 17 species (12 genera) at two elevations (200 and 1500 m) in the Colombian Andes. In addition, we examined the influence of body size (intertegular distance, ITD), hairiness (thoracic hair length) and coloration (lightness value) on bees' thermal tolerance. Because stingless beekeepers often relocate their colonies across the altitudinal gradient, as an initial attempt to explore potential social responses to climatic variability, we also tracked for several weeks brood temperature and humidity in nests of three species at both elevations. We found that CTMin decreased with elevation while CTMax was similar between elevations. CTMin and CTMax increased (low cold tolerance and high heat tolerance) with increasing ITD, hair length and lightness value, but these relationships were weak and explained at most 10% of the variance. Neither CTMin nor CTMax displayed significant phylogenetic signal. Brood nest temperature tracked ambient diel variations more closely in the low-elevation site, but it was constant and higher at the high-elevation site. In contrast, brood nest humidity was uniform throughout the day regardless of elevation. The stronger response in CTMin, and a similar CTMax between elevations, follows a pattern of variation documented across a wide range of taxa that is commonly known as the Brett's heat-invariant hypothesis. Our results indicate differential thermal sensitivities and potential thermal adaptations to local climate, which support ongoing conservation policies to restrict the long-distance relocations of colonies. They also shed light on how malleable nest thermoregulation can be across elevations. [ABSTRACT FROM AUTHOR]

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Hybrid dacite magmas from Taápaca volcano in the Central Andean Volcanic Zone (18°S, northern Chile) contain sanidine crystals of unusual size (1–12 cm) and abundant mafic enclaves of variable composition throughout the entire eruptive history (1·5 Ma to recent) of the volcano. They are rich in mineral inclusions and strongly zoned in Ba with distinct growth bands separated by resorption interfaces. Resorption is followed by a sudden increase in Ba with compositional contrasts up to 2·3 wt% BaO. We argue that resorption and the sharp jumps in Ba concentration reflect distinct heating and melting events, suggesting that different growth zones formed at different temperatures. Amphibole–plagioclase thermobarometry based on mineral inclusions gives variable temperatures of ∼720–820 °C at shallow pressures (0·1–0·3 GPa) for individual growth zones. Using these temperatures for diffusion modelling, Ba profiles from X-ray scanning profiles and grey-scale gradients based on accumulated back-scattered electron images across these interfaces allow us to estimate crystal residence and reactivation times prior to eruption. This temperature control allowed the application of a 'non-isothermal' diffusion algorithm to obtain diffusion times for individual diffusive boundaries that range from 0·4 to 490 kyr and add up to total residence times of 9–499 kyr for different crystals from different stages of eruption. A combination of temperatures, pressure, diffusion times and R-MELTS modelling of the parent rhyodacite suggests storage conditions for the Taápaca reservoir at near eutectic composition at shallow depth (4–10 km). Temperatures never fell below the magma solidus but frequently cycled between 720 °C and 820 °C (i.e. between eruptible and non-eruptible state with crystallinity circling around ∼40–50 vol%) for tens to hundreds of thousands of years. We define this as 'long-term transitional temperature cycling' or LTTC storage. Frequent recharge events of basaltic andesite magma, as represented by abundant mafic enclaves, orchestrated the temperature cycling, resulted in multiple heating events that caused frequent resorptions and interrupted crystal growth, and kept the reservoir thermally 'alive'. Recharge events became more frequent only ∼3–11 kyr before the eventual eruption that carried a particular set of sanidine megacrysts to the surface. Thus, after many earlier recharge events that did not result in eruption, a final event involved mixing at a critical recharge rate to mobilize, entrain, and erupt a particular set of megacrysts from the resident rhyodacite in a hybrid dacite host. This process, happening not more than a few centuries before an eruption, has been repeated at similar time-scales at different stratigraphic stages throughout the 1·5 Myr history of Taápaca volcano. The observed mineral zonation patterns and size of sanidine crystals from the resident magma reservoir below Taápaca volcano are identical to those observed in the megacrysts from granite intrusions that also show typical age ranges of zircon crystallization that are comparable with the residence times extracted here from Ba zonation. Taápaca sanidines thus may represent an erupted equivalent and provide 'smoking gun' evidence of temperature cycling during the formation of such K-feldspar megacrysts in granites. [ABSTRACT FROM AUTHOR]

The Andean uplift is recognized as one of the most important events shaping the Neotropical biota. Previous phylogenetic reconstructions of Nasa , a mostly tropical Andean genus, have been unable to address its historical biogeography or ancestral character estimations in detail due to insufficient sampling and phylogenetic resolution. The main goal of the present study is to provide an expanded and highly resolved phylogenetic reconstruction of the genus to address these questions. We were able to sequence 87 of the 125 taxa (species and subspecies) of Nasa , for the plastid markers trnL–trnF , matK , trnS–trnG and rps16. Our results show that Nasa falls into four well-supported clades, clade I is sister to the rest of the genus and is composed of Central Andean species. The remaining three clades are more widely distributed, found also in the Amotape-Huancabamba Zone (AHZ) and the northern Andes. Our morphological analyses were able to identify plausible phylogenetic affinities of most Nasa spp. for which molecular data are unavailable, with three of the morphological clusters composed mostly by species of three well-supported clades (Clades II, III and IV). Historical biogeography indicates that Nasa has a history spanning 50 Myr, its early events predating most of the Andean uplift. Nasa appears to have originally occupied mid-elevation, seasonally dry habitats. By the mid-Miocene (c. 15 Mya) expansion into new forest edge and undergrowth habitats took place. This coincides with renewed uplift that increased the complexity of the abiotic conditions in the Andes. The AHZ is retrieved as the most important centre of diversification since the closure of the West Andean Portal and appears to be a cradle of clades of Nasa. Conversely, the central Andes, the most likely area of origin of the genus, house mostly ancient, species-poor clades. [ABSTRACT FROM AUTHOR]

Pabstiella consists of c. 130 epiphytic species in the Neotropics. We present a phylogenetic analysis based on nrITS, matK and trnH-psbA sequences from 59 species of the genus and 40 Pleurothallidinae and two Laeliinae and one Bletiinae as an outgroup, using maximum likelihood, Bayesian inference and maximum parsimony. We also performed molecular dating, biogeographical analyses and ancestral morphological character reconstruction. Our results confirm the monophyly of Pabstiella with strong support. Ten clades are inferred and are herein proposed as sections. Pabstiella originated in the Andes and the Atlantic Rainforest in the Late Miocene (c. 7.93 Mya) in an epoch when these biomes were probably connected. A main vicariance event divided an early-diverging lineage that inhabited the Andes from an Atlantic Rainforest lineage that diversified in this region during the Pliocene and Pleistocene, mainly in the Serra do Mar in south-eastern Brazil. Our findings also suggest that the Atlantic Rainforest may have played an important role in the origin of subtribe Pleurothallidinae. The morphological character reconstruction showed high levels of homoplasy, with few recognized synapomorphies associated with stems and petals. Other characters related to the habit and stems were identified as important in the evolutionary history of the genus. [ABSTRACT FROM AUTHOR]

The Vampyressa melissa species complex comprises three rare bat species poorly represented in museum collections. Vampyressa melissa and V. sinchi are restricted to the eastern slope of the Andes, while V. elisabethae only is known from Panama, in Central America. The species complex has received recent attention in terms of systematic reviews, which concluded in the description of two species: one from Panama (V. elisabethae) and one from Colombia (V. sinchi). Vampyressa melissa recently was reported from the eastern slopes of the Cordillera Oriental of Colombia, in the department of Casanare. However, morphological and genetic (Cytochrome b) comparisons showed that these specimens belong to an undescribed species of the genus. The new species is the smallest member of the V. melissa complex and has a unique set of morphological characters compared to other Vampyressa species. Molecular evidence shows that the new species is sister to V. melissa (sensu stricto) from Colombia and Peru, albeit with high genetic divergence (7.9%). Nevertheless, Cytochrome b sequences of V. elisabethae and V. sinchi still are unknown. This new species increases to six the number of species in the genus. Vampyressa melissa , V. sinchi , and the new species, exhibit restricted distributions in the eastern slopes of the Andean Cordillera, in specific altitudinal ranges. Because of geographic constraints, their biological rarity, and the high deforestation rates in their distributional area, we suggest that these three species must be considered as taxa threatened with extinction. [ABSTRACT FROM AUTHOR]

Cryptic species, defined as those that are morphologically indistinguishable but phylogenetically distinct, are common in bats and correspond to the majority of newly described species. Such seems to be the case of Glossophaga soricina , a generalist, glossophagine bat that is broadly distributed throughout the Neotropics. Several studies have found high levels of molecular variation within G. soricina , suggesting that it could be a cryptic species complex. Here, we explore data derived from two-dimensional geometric morphometric analyses of cranial characters and their covariation with environmental variables, aiming to test the existence of more than one species grouped within it and to contribute to the knowledge of its variation and evolutionary history. Variation in shape and size of skull and mandible supports the two main mitochondrial lineages reported in previous studies, one corresponding to the east side of the Andes (subspecies G. s. soricina) and the other one corresponding to populations from Mesoamerica and the west side of the Andes, in turn composed of at least three monophyletic and morphologically differentiated taxa. Environmental variables correlate with shape variation and might be responsible for convergences in shape and size between the species with the smallest distributions. Based on the evidence we present in this work we elevate four subspecies to the taxonomic level of species. The correct names for the species of the analyzed complex are: G. soricina (Pallas 1766), G. mutica Merriam 1898, G. antillarum Rehn 1902, and G. valens Miller 1913. [ABSTRACT FROM AUTHOR]

The tropics of the New World are a biodiversity hotspot, the genus Anthurium being an example of a megadiverse taxon with currently > 1000 described species. In this study, we provide detailed information on species distributions and analyse patterns of diversity and endemism, with a particular focus on the comparison of epiphytic and terrestrial congenerics. Using a dataset of occurrence records for 1041 Anthurium spp. (c. 98% of the genus), we modelled geographical species distributions using climate-based species distribution models or buffered convex hulls depending on the number of occurrences available. We identified nine bioregions using cluster analysis. The Andean slopes, Central America, the Chocó and the Atlantic Forest in eastern Brazil are the most important centres of diversity for Anthurium , whereas endemism is highest in the central Andes. These macroecological patterns agree largely with diversity centres for other Neotropical plant groups. Epiphytes, accounting for about two-thirds of all species, have much larger range sizes than terrestrials, but do not differ in elevational ranges. Almost 40% of all Anthurium spp. are restricted to the lowlands, but a few species grow at elevations of almost 4000 m. Although individual species have an average elevation range of just c. 1000 m, there are taxa that cover > 3500 m of elevation. [ABSTRACT FROM AUTHOR]

Aims Seed dispersal by endozoochory is an important process in plant regeneration and the establishment of new populations. Seeds with dormancy may especially benefit after disperser gut passage. However, the ways in which gut passage affect the germination of plant species with physiological dormancy remain unclear. Here, we experimentally assessed the mutualistic interaction between the Austral parakeet (Enicognathus ferrugineus) as a disperser of calafate (Berberis microphylla), a thorny bush inhabiting the understory of the Austral temperate forests of South America with seeds that are characterized by deep physiological dormancy. Methods Germination success and viability of calafate seeds obtained from faeces and from intact fruits were tested under four treatments: (i) digested seeds, (ii) digested seeds with faecal extract, (iii) intact seeds from fruit and (iv) intact seeds from fruit with pulp. Important Findings About 65% of the Austral parakeet droppings contained calafate seeds. Viability of seeds did not differ between treatments. However, germination was significantly higher in digested seeds than in intact seeds from fruits, while no difference was found between faecal and pulp extracts. Neither faecal matter nor fruit pulp provided seeds with any ecological advantages derived from enhancing germinability, but did confer some disadvantage in germination time. Faecal matter is expected to be completely lacking around seeds after several months under snow before germinating in the following spring, given intense washing due to persistent rain and the spring thaw in the Patagonian Andes. The higher germinability along with faster germination of digested seeds supports the hypothesis of a legitimate mutualistic interaction between Austral parakeets and calafate. We hypothesized that the passage through the disperser digestive tract might break physiological dormancy as differences in germinability between ingested and non-ingested seeds. Our results highlight the relevant role of endozoochory in plant species with physiological dormancy living in highly seasonal environments. [ABSTRACT FROM AUTHOR]

Many Orchidaceae, especially those occupying periodically dry, epiphytic microhabitats in the humid tropics, are believed to engage in the water-conserving crassulacean acid metabolism (CAM) photosynthetic pathway. However, the photosynthetic pathway has been studied in only c. 5% of all orchid species. Here we extend the survey to 1079 orchid species, mainly from Colombia, by assessing the presence of CAM based on the carbon isotopic signature (δ 13C values) of herbarium specimens. Ninety-six species, representing 8.9% of those analysed, had δ 13C values less negative than −20‰, indicating CAM. Epiphytism was the predominant life form (75.2% of species sampled), and 9.4% of these epiphytes showed a CAM-type isotopic signature. Isotope values suggested CAM in 19 terrestrial orchid species, 14 species from high elevation (2000–3400 m) and species from six genera that were previously unknown to engage in CAM (Jacquiniella , Meiracyllium , Pabstiella , Psychopsis , Pterostemma and Solenidium). We conclude that CAM is the major pathway of carbon acquisition in a small but broadly distributed fraction of tropical orchids and is more prevalent at lower elevations. [ABSTRACT FROM AUTHOR]

Orogenic plateaus can exist in a delicate balance in which the buoyancy forces due to gravity acting on the high topography and thick crust of the plateau interior are balanced by the compressional forces acting across their forelands. Any shortening or extension within a plateau can indicate a perturbation to this force balance. In this study, we present new observations of the kinematics, morphology and slip rates of active normal faults in the South Peruvian Altiplano obtained from field studies, high-resolution DEMs, Quaternary dating and remote sensing. We then investigate the implications of this faulting for the forces acting on the Andes. We find that the mountains are extending ∼NNE–SSW to ∼NE–SW along a normal fault system that cuts obliquely across the Altiplano plateau, which in many places reactivates Miocene-age reverse faults. Radiocarbon dating of offset late Quaternary moraines and alluvial fan surfaces indicates horizontal extension rates across the fault system of between 1 and 4 mm yr–1—equivalent to an extensional strain rate in the range of 0.5–2 × 10−8 1 yr–1 averaged across the plateau. We suggest the rate and pattern of extension implies there has been a change in the forces exerted between the foreland and the Andes mountains. A reduction in the average shear stresses on the sub-Andean foreland detachment of ≲4 MPa (20–25 per cent of the total force) can account for the rate of extension. These results show that, within a mountain belt, the pattern of faulting is sensitive to small spatial and temporal variations in the strength of faults along their margins. [ABSTRACT FROM AUTHOR]

Subtribe Vrieseinae comprise four genera, Alcantarea , Stigmatodon , Vriesea s.s. and Waltillia , encompassing c. 20% of species in Tillandsioideae (Bromeliaceae), almost all of which are exclusive to Brazil. Here, we explore the biogeographic history of Vrieseinae, sampling 21 of the 22 genera of Tillandsioideae (130 terminals) and three DNA sequence markers (two plastid: rps16-trnK and matK ; one nuclear: PHYC). We inferred a dated phylogeny and the ancestral areas of this lineage through RASP (reconstruct ancestral state in phylogeny) analyses. Vrieseinae were recovered as monophyletic, but tribe Vrieseeae (subtribe Vrieseinae + subtribe Cipuropsidinae) were not. A vicariant event between the Andes and Brazilian Shield probably occurred c. 10 Mya, when two clades, Cipuropsidineae + Tillandsieae and Vrieseineae, diverged. The Atlantic Forest plus the Chacoan region is recognized as the ancestral area for Vrieseinae. The results confirmed the recent origin of genera of Vrieseinae, with estimated crown ages in the Pliocene (5.3–2.6 Mya). We propose that the Paranaean Sea influenced the divergence of the main clades; Pleistocene events were probably responsible for the diversification of the most recent clades. This study sheds light on the biogeographic history of a key group of Neotropical plants, providing a new hypothesis for the evolution of bromeliads. [ABSTRACT FROM AUTHOR]

Identifying the traits causing reproductive isolation and the order in which they evolve is fundamental to understanding speciation. Here, we quantify prezygotic and intrinsic postzygotic isolation among allopatric, parapatric, and sympatric populations of the butterflies Heliconius elevatus and Heliconius pardalinus. Sympatric populations from the Amazon (H. elevatus and H. p. butleri) exhibit strong prezygotic isolation and rarely mate in captivity; however, hybrids are fertile. Allopatric populations from the Amazon (H. p. butleri) and Andes (H. p. sergestus) mate freely when brought together in captivity, but the female F1 hybrids are sterile. Parapatric populations (H. elevatus and H. p. sergestus) exhibit both assortative mating and sterility of female F1s. Assortative mating in sympatric populations is consistent with reinforcement in the face of gene flow, where the driving force, selection against hybrids, is due to disruption of mimicry and other ecological traits rather than hybrid sterility. In contrast, the lack of assortative mating and hybrid sterility observed in allopatric populations suggests that geographic isolation enables the evolution of intrinsic postzygotic reproductive isolation. Our results show how the types of reproductive barriers that evolve between species may depend on geography. [ABSTRACT FROM AUTHOR]

In this study, we address the evolutionary relationships and discuss the biogeographical history of a complex and diverse group of ovenbirds, the Thripophagini. We reconstruct the phylogeny and estimate the time of divergence of this group, using sequences from two complete mitochondrial genes (cytochrome b and NADH subunit 2) from a total of 115 fresh tissue samples. The results provide a better understanding of the phylogenetic relationships of the taxa within this group, some of which require a thorough taxonomic revision. We discuss the biogeographical history of the group, and find parallels with other previously studied Andean birds which may indicate that tectonic and climatic events might, at least in part, be linked to its diversification through the uplift of the Andes, the creation of new montane habitats and barriers, the evolution of Amazonian drainages and landscapes, and the climatic oscillations of the Pleistocene. [ABSTRACT FROM AUTHOR]

High-elevation organisms experience shared environmental challenges that include low oxygen availability, cold temperatures, and intense ultraviolet radiation. Consequently, repeated evolution of the same genetic mechanisms may occur across high-elevation taxa. To test this prediction, we investigated the extent to which the same biochemical pathways, genes, or sites were subject to parallel molecular evolution for 12 Andean hummingbird species (family: Trochilidae) representing several independent transitions to high elevation across the phylogeny. Across high-elevation species, we discovered parallel evolution for several pathways and genes with evidence of positive selection. In particular, positively selected genes were frequently part of cellular respiration, metabolism, or cell death pathways. To further examine the role of elevation in our analyses, we compared results for low- and high-elevation species and tested different thresholds for defining elevation categories. In analyses with different elevation thresholds, positively selected genes reflected similar functions and pathways, even though there were almost no specific genes in common. For example, EPAS1 (HIF2α), which has been implicated in high-elevation adaptation in other vertebrates, shows a signature of positive selection when high-elevation is defined broadly (>1,500 m), but not when defined narrowly (>2,500 m). Although a few biochemical pathways and genes change predictably as part of hummingbird adaptation to high-elevation conditions, independent lineages have rarely adapted via the same substitutions. [ABSTRACT FROM AUTHOR]

Maca (Lepidium meyenii), a Brassicaceae herb plant originated from Andean mountains, has attracted wide interests due to its unique health benefits in reproduction and fertility. Because of its adaptation to the 4000 m high-altitude harsh environment, maca is attracting more and more attention from both crop breeders and basic biologists. After our previous release of the maca genome sequence, there's a growing need to store, query, analyze and integrate various maca resources efficiently. Here, we created Maca Genome Hub (MGH), a genomics and genetics database of maca. Currently, the MGH V1.0 harbors the genome sequence, predicted coding sequences and protein sequences, various annotations, markers and expression data. For the maca research community, we also provided the publications, researchers and related news. MGH is designed to enable users' easy access to analyze, retrieve and visualize the genomic or genetic information through a series of online tools, including the Basic Local Alignment Search Tool, the JBrowse, the query system, the synteny tool and the data downloads. These integrated heterogeneous data, tools and interfaces in MGH allow efficient mining of the latest genomics and genetics data. We hope that MGH will accelerate the research and development in maca. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mammalogy is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The pre- and current collision of the Juan Fernández Ridge with the central Chilean margin at 31°-33°S is characterized by large-scale crustal thinning and long-term subsidence of the submarine forearc caused by subduction erosion processes. Here, we study the structure of the central Chilean margin in the ridge-trench collision zone by using wide-angle and multichannel seismic data. The transition from the upper to middle continental slope is defined by a trenchward dipping normal scarp with variable offsets of 500-2000 m height. Beneath the scarp, the 2-D velocity-depth models show a prominent lateral velocity contrast of >1 s-1 that propagates deep into the continental crust defining a major lateral seismic discontinuity. The discontinuity is interpreted as the lithological contact between the subsided/collapsed outermost forearc (composed of eroded and highly fractured volcanic rocks) and the seaward part of the uplifted Coastal Cordillera (made of less fractured metamorphic/igneous rocks). Extensional faults are abundant in the collapsed outermost forearc, however, landward of the continental slope scarp, both extensional and compressional structures are observed along the uplifted continental shelf that forms part of the Coastal Cordillera. Particularly, at the landward flank of the Valparaíso Forearc Basin (32°-33.5°S), shallow crustal seismicity has been recorded in 2008-2009 forming a dense cluster of thrust events of Mw 4-5. The estimated hypocentres spatially correlate with the location of the fault scarp, and they highlight the upper part of the seismic crustal discontinuity. [ABSTRACT FROM AUTHOR]

The reciprocal illumination nature of integrative taxonomy through hypothesis testing, corroboration and revision is a powerful tool for species delimitation as more than one source has to support the hypothesis of a new species. In this study, we applied an integrative taxonomy approach combining molecular and morphological data sets with distributional patterns to examine the level of differentiation between and within the grasshopper Orotettix species. Orotettix was described based on five valid species distributed in the Andes of Peru. In our study, initially a molecular-based hypothesis was postulated and tested against morphological data and geographical patterns of distribution. Results from molecular and morphological analyses showed agreement among the species delimitation in Orotettix, and were also consistent with the geographical distribution. The analyses allowed us to delimit five new species for the genus ( O. lunatus sp. nov., O . astreptos sp. nov., O. colcaensis sp. nov., O . paucartambensis sp. nov. and O . dichrous sp. nov.) from the Eastern and Western Cordilleras of Peru. We also provide critical knowledge on the phylogenetic relationships and distribution of the genus and conduct a revision of Orotettix. © 2015 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mammalogy is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The amphibian genus Telmatobius is a diverse group of species that inhabits the Andes. This study analysed the phylogenetic relationships of 19 species described from the central Andes of Chile and Bolivia, and 12 undescribed populations of Chile. A molecular phylogeny based on mitochondrial DNA 16S and cytochrome b shows that the Chilean species belong to three groups: (1) the Telmatobius marmoratus group, widespread in the Chilean and Bolivian Altiplano; (2) the Telmatobius hintoni group, including the species Telmatobius philippii, Telmatobius fronteriensis, and Telmatobius huayra, occurring in the south-western Altiplano of Chile and Bolivia, and (3) the Telmatobius zapahuirensis group, a new clade which also includes Telmatobius chusmisensis, Telmatobius dankoi, and Telmatobius vilamensis, restricted to western slopes of the Andes, and which was recovered as more closely related to the T. hintoni group than the T. marmoratus group. The divergence times between clades were traced to the late Pleistocene. The molecular phylogeny also confirmed that the groups of the Altiplano and western Andes slopes form a clade separated from the species that inhabit the eastern Andes ( Telmatobius verrucosus and Telmatobius bolivianus groups), supporting the forest origin of the Altiplano groups proposed by several previous authors. © 2014 The Linnean Society of London [ABSTRACT FROM AUTHOR]

The recognition of areas of endemism ( AEs) is important for conservation biology and biogeographical regionalization. Our objective was to quantitatively identify AEs and distributional congruence patterns of native rodents at the tropical/temperate transition in the central Andes. We analysed 6200 geo-referenced distributional records of 80 species in north-western Argentina using NDM/ VNDM software. We found 20 AEs defined by 22 endemic species (27% of the total rodent fauna) and 34 patterns of distributional congruence in non-endemic rodents. Geographical range congruence follows two main patterns running parallel along the Andes. One is related to the humid eastern slopes of the Andes ( Argentinean Yungas forest) and the other to the high Andes ( Argentinean Puna plateau). Endemism was mainly restricted to the southernmost part of the Yungas forest and adjacent dryer valleys ( Monte desert). Species diversity was highest in the northern sector of the Argentinean Yungas forest, where several species reach their southern distributional range. This incongruence among hotspots of diversity and endemism has also been also noted in diversity studies at continental and global scales. Our results provide a starting point for conservation planning in the southernmost Central Andes, which combines the taper of tropical diversity and range-restricted species endemic to the tropical-temperate transition. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112, 163-179. [ABSTRACT FROM AUTHOR]

Glassy, plagioclase phenocryst-free, ∼7–3 Ma, andesitic lavas erupted at the southern end of the Andean Central Volcanic Zone (CVZ) at 27–28·5°S are argued to contain a component from continental crust that was incorporated into the sub-arc mantle in a major pulse of fore-arc subduction erosion that removed ∼50 km of fore-arc. The 7–3 Ma amphibole-bearing Pircas Negras (54–64% SiO2) and ∼7·7 Ma pyroxene-bearing Dos Hermanos lavas erupted as the frontal arc was displaced some 50 km eastward over a developing bend in the Wadati–Benioff zone at the northern margin of the Chilean–Pampean flat-slab region. Their chemistry differs from that of older Miocene and younger CVZ arc lavas in the region in having more pronounced high field strength element (La/Ta = 40–100; Ba/Ta = 800–2400) and heavy rare earth element (Sm/Yb ∼ 4–9) depletions and an extreme adakitic-like character (∼600–1400 ppm Sr; Sr/Yb ∼ 400–1350). They also differ from older Miocene lavas in having higher 87Sr/86Sr and lower 143Nd/143Nd at the same wt % SiO2, while still showing trends with increasing wt % SiO2 that are best attributed to contamination in the ∼65–70 km thick crust. Overall, the trace element and isotopic features of the Pircas Negras lavas are consistent with modeling that attributes differences from older and younger lavas to enrichment of the arc mantle wedge by partial melts of tectonically eroded fore-arc crust, with the modeled eroded component being an outcrop and geophysically constrained mixture of 80–90% Jurassic mafic magmatic rocks and 10–20% silicic Paleozoic crust. An adakitic-type partial melt of this eroded crust generated at >2 GPa, reacted with mantle peridotite, can explain the high Mg# values (50–61) and Cr (100–350 ppm) and Ni (40–70 ppm) contents in some 5–3 Ma Pircas Negras lavas. Pre-eruption temperatures over 1060°C, calculated from mineral thermometry and the MELTS program, permit these magmas to subsequently melt and react with overlying eclogitic crust. Magma storage in this thick crust then led to amphibole crystallization and suppression of plagioclase fractionation. Quartz and feldspar xenocrysts were acquired from locally pooled mid-crustal magmas and the silicic upper crustal basement during final rapid ascent to the surface. Given a constant arc–trench gap of 300 km over the last 10 Myr, ∼198 km3 Myr–1 km–1 of fore-arc crust needs to be removed by subduction erosion at 8–3 Ma to account for the material balance of the fore-arc crust. [ABSTRACT FROM AUTHOR]

Phylogeography in combination with ecological niche modeling (ENM) is a robust tool to analyze hypotheses on range shifts under changing climates particularly of taxa and areas with scant fossil records. We combined phylogeographic analysis and ENM techniques to study the effects of alternate cold and warm (i.e., glacial and interglacial) periods on the subtropical montane cold-tolerant conifer Podocarpus parlatorei from Yungas forests of the central Andes. Twenty-one populations, comprising 208 individuals, were analyzed by sequences of the trnL–trnF cpDNA region, and 78 sites were included in the ENM. Eight haplotypes were detected, most of which were widespread while 3 of them were exclusive of latitudinally marginal areas. Haplotype diversity was mostly even throughout the latitudinal range. Two distribution models based on 8 bioclimatic variables indicate a rather continuous distribution during cooling, while under warming remained within stable, yet increasingly fragmented, areas. Although no major range shifts are expected with warming, long-lasting persistence of cold-hardy taxa inhabiting subtropical mountains may include in situ and ex situ conservation actions particularly toward southern (colder) areas. [ABSTRACT FROM PUBLISHER]

The article presents a study which aims to document the species richness (diversity) and host associations of family Tachinidae, flies that are known to attack the larval Lepidoptera. The study collected samples around the Yanayacu Biological Station and Center for Creative Studies (YBS) in northeastern Ecuadorian Andes. Results show that most of the tachinid species are relatively centered on a single or a number of related hosts, but the sampling was inadequate to determine the host range.

Copyright of Journal of Mammalogy is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Estimates of effective elastic thickness for the western portion of the South American Plate using, independently, forward flexural modelling and coherence analysis, suggest different thermomechanical properties for the same continental lithosphere. We present a review of these estimates and carry out a critical reappraisal using a common methodology of 3-D finite element method to solve a differential equation for the bending of a thin elastic plate. The finite element flexural model incorporates lateral variations of and the Andes topography as the load. Three maps for the entire Andes were analysed: Stewart & Watts (1997) , Tassara et al. (2007) and Pérez-Gussinyé et al. (2007) . The predicted flexural deformation obtained for each map was compared with the depth to the base of the foreland basin sequence. Likewise, the gravity effect of flexurally induced crust–mantle deformation was compared with the observed Bouguer gravity. estimates using forward flexural modelling by Stewart & Watts (1997) better predict the geological and gravity data for most of the Andean system, particularly in the Central Andes, where ranges from greater than in the sub-Andes to less than under the Andes Cordillera. The misfit between the calculated and observed foreland basin subsidence and the gravity anomaly for the Marañon basin in Peru and the Bermejo basin in Argentina, regardless of the assumed map, may be due to a dynamic topography component associated with the shallow subduction of the Nazca Plate beneath the Andes at these latitudes. [ABSTRACT FROM AUTHOR]

Hypotheses on the taxonomic status of two Bolivian Pristimantis with taxonomic problems are assessed by an integrative taxonomic approach that integrates three independent lines of evidence: external morphology, prezygotic reproductive barriers (advertisement calls) and reciprocal monophyly (phylogenetic analyses of partial 16S mtDNA sequences). Central Andean Bolivian populations previously assigned to either P. peruvianus or P. dundeei, and lowland Amazonian populations from southern Peru and northern Bolivia previously considered P. peruvianus do not correspond to these species. Indeed, multivariate analyses of qualitative and quantitative morphological and bioacoustic characters, and phylogenetic analyses support the hypothesis that they represent different, previously unknown, cryptic lineages. They are herein described as new species. The former is a sibling species of P. fenestratus that inhabits the Amazonian and semideciduous forests of the Andean foothills in central Bolivia. The latter is sibling to the Andean species P. danae and is parapatric to it in the Amazonian lowland forests and adjacent foothills of northern Bolivia, southern Peru and adjacent Brazil. Most species of Neotropical frogs, and especially Pristimantis, have been described by using external qualitative morphological characters only. An extended integrative taxonomic approach, as exemplified herein, may lead to the discovery of many other cryptic and sibling lineages that would increase the species numbers of tropical areas. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155, 97–122. [ABSTRACT FROM AUTHOR]

We have used the S wave receiver function (SRF) technique to investigate the crustal thickness beneath two seismic profiles from the CHARGE project in the southern central Andes. A previous study employing the P wave receiver function method has observed the Moho interface beneath much of the profiles. They found, however, that the amplitude of the P to S conversion was diminished in the western part of the profiles and have attributed it to a reduction of the impedance contrast at the Moho due to lower crustal ecologitization. With SRF, we have successfully detected S to P converted waves from the Moho as well as possible conversions from other lithospheric boundaries. The continental South American crust reaches its maximum thickness of ∼70 km (along 30°S between 70°W and 68.5°W) beneath the Principal Cordillera and the Famatina system and becomes thinner towards the Sierras Pampeanas with a thickness of ∼40 km. Negative phases, possibly related to the base of the continental and oceanic lithosphere, can be recognized in the summation traces at different depths. By comparing our results with data obtained from previous investigations, we are able to further constrain the thickness of the crust and lithosphere beneath the central Andes. [ABSTRACT FROM AUTHOR]

A new genus and species of microhylid frogs are described from localities at elevations of 2500–2960 m on the eastern slopes of the Andes in central Peru. These are the first microhylids recorded from the Peruvian Andes and they differ from all other neotropical microhylids by their lack of a tympanum, tympanic annulus and stapes. Phrynopus carpish is removed from Leptodactylidae and placed in Microhylidae. Several novel morphological characters for microhylids are described, among them dermal body spines, expanded nuptial pads in males and heterotopic cartilages. Osteological descriptions and comparison of the new genus with Nelsonophryne revealed a number of intriguing characters that may prove to be useful in phylogenetic studies. Among these are the presence of a double, rather than single, wall between the olfactory capsules in one genus and the presence of a pair of previously undescribed bones in the nasal capsules of one species in each genus. In addition, some of these taxa have spinous projections on the ventral surface of the hyoid plates, and one species has only seven presacral vertebrae, owing to the fusion of Presacrals I and II. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149, 583–609. [ABSTRACT FROM AUTHOR]

On 2005 June 13, a major earthquake (M7.8) occurred in the Tarapaca region (North Chile), within the region of high mountains. At large distances from the epicentre, this event produced coherent infrasonic waves detected by three infrasound stations that are part of the International Monitoring System. The observed azimuth variations and the long signal durations suggest that wide regions in the Andes Mountains radiated infrasonic waves. From these observations, the main sources' regions are reconstructed. Such an event recorded by multiple stations offers an unique opportunity to evaluate the relative contributions of the different source mechanisms involved in large earthquakes as well as to improve our understanding of the amplification of ground displacement caused by the topography. With a review of infrasound signals from past earthquakes, extended empirical scaling relations are derived. We show that beyond the seismic magnitude, both seismic source and topographic features also play a predominant role in the generation of infrasound. [ABSTRACT FROM AUTHOR]

Upper Palaeozoic silicic magmatism is widespread in the Central Andes, but its origin is poorly constrained. We investigated whole-rock chemical and isotopic composition of Upper Palaeozoic granitoids and their Early Palaeozoic high-grade country rocks in the Chilean Coastal Cordillera and Precordillera at ~22°S, in comparison with an Upper Cretaceous granitoid. The age of the Late Palaeozoic granitoids from a Rb-Sr isochron of ~300 Ma is consistent with K-Ar cooling ages of hornblende and biotite. Similar major and trace element patterns as well as Nd and Pb isotopic composition of Upper Palaeozoic granitoids and gneisses point to a source of the granitoids that is similar to the gneisses at outcrop. Sr isotope ratios of the Upper Palaeozoic granitoids are less radiogenic than those in many of the gneisses. We propose a stratification of the Early Palaeozoic crust with a Rb-deficient granulitic mid-lower crust, resulting in less radiogenic Sr compared with the upper crust, based on the interpretation of the P-T-t history and isotopic composition of the Lower Palaeozoic metamorphic basement and of the isotopic composition of the Late Palaeozoic granitoids and younger magmatic rocks. Nd isotopic composition is identical in lower and upper crust and in crustal melts from the Late Palaeozoic to Recent. The Cretaceous granitoid evolved from partial melts of a mantle-derived source with considerable contamination by the old crustal component. The crust that formed in the Early Palaeozoic is the major source of material for the Cenozoic tectonic thickening of the Andean crust. [ABSTRACT FROM PUBLISHER]

Under intraspecific differentiation driven by differential climatic adaptation, it may be expected that intraspecific genetic groups occur at distinct environments. Populations occupying different niches may therefore differ in their ability to cope with climate change. Here, we addressed this hypothesis with a wild tomato, Solanum pimpinellifolium. This species is distributed from the west side of Andes to the coastal region in Peru and Ecuador and occupies a wide environmental diversity. This environmental diversity is related to the genetic structure of the species providing an ideal material to investigate the isolation by environment hypothesis. While previous hypothesis stated that S. pimpinellifolium originated from northern Peru and migrated northwards and southwards, our results support that S. pimpinellifolium originated from Ecuador and expanded to northern and southern Peru, and during this process, the niche space of S. pimpinellifolium became more associated with cold and drought. We further predicted its fate under anthropogenic climate change. According to our predictions, the northern group will maintain its current extent or even expand to the entire western region of Ecuador. In contrast, we predicted low habitat suitability for the southern group which could potentially lead to the shrinkage of its distribution. In conclusion, we revealed the distinct fates among the differentiated populations driven by environment under global warming conditions. [ABSTRACT FROM AUTHOR]