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The major histocompatibility complex (MHC) is a genetic region in jawed vertebrates that contains key genes involved in the immune response. Associations between the MHC and avian malaria infections in wild birds have been observed and mainly explored in the Northern Hemisphere, while a general lack of information remains in the Southern Hemisphere. Here, we investigated the associations between the MHC genes and infections with Plasmodium and Haemoproteus blood parasites along a latitudinal gradient in South America. We sampled 93 rufous-collared sparrows (Zonotrichia capensis) individuals from four countries, Colombia, Ecuador, Peru, and Chile, and estimated MHC-I and MHC-II allele diversity. We detected between 1-4 (MHC-I) and 1-6 (MHC-II) amino acidic alleles per individual, with signs of positive selection. We obtained generalized additive mixed models to explore the associations between MHC-I and MHC-II diversity and latitude. We also explored the relationship between infection status and latitude/biome. We found a non-linear association between the MHC-II amino acidic allele diversity and latitude. Individuals from north Chile presented a lower MHC genetic diversity than those from other locations. We also found an association between deserts and xeric shrublands and a lower prevalence of Haemoproteus parasites. Our results support a lower MHC genetic in arid or semi-arid habitats in the region with the lower prevalence of Haemoproteus parasites.

Twenty-five years since foundational publications on valuing ecosystem services for human well-being1,2, addressing the global biodiversity crisis3 still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever4. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF)5 and the UN Sustainable Development Goals6, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature7. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change8, pandemic emergence9 and socio-environmental injustices10. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions7,11. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.

•Background:Plot-based monitoring has yielded much information on the taxonomic diversity and carbon (C) storage in tropical lowland forests of the Amazon basin. This has resulted in an improved understanding of the relationship between lowland forest biomass dynamics and global change drivers, such as climate change and atmospheric CO2 concentration. Much less attention has been paid to the mountain ecosystems of South America that comprise montane forests and alpine vegetation (páramo, puna, high Andean grasslands, wetlands, and alpine heath). This vegetation complex provides a variety of ecosystem services and forms a natural laboratory along various physiographic, geological and evolutionary history/biogeography, and land use history gradients. •Aims: Here, we review existing empirical understanding and model-based approaches to quantify the contribution of mountain ecosystems to ecosystem service provision in the rapidly changing socioecological setting of the South American mountains. The objective of this paper is to outline a broad road map for the implementation of mountain vegetation into dynamic global vegetation models (DGVM) for use in Earth System Models (ESM), based on our current understanding of their structure and function and of their responsiveness to global change drivers. We also identify treeline processes, critical in mountain ecosystems, as key missing elements in DGVMs/ESMs, and thus explore in addition a treeline model. •Methods: Stocktaking of the availability of empirical data was undertaken from eight research sites along the Andes and in south-eastern Brazil. Out of eight sites, two (one each in Venezuela and Brazil) had some climate, ecological and ecophysiological data potentially suitable to parametrise a DGVM. Tree biomass data were available for six sites. A preliminary assessment of the Joint UK Land Environment Simulator (JULES) DGVM was made to identify gaps in available data and their impacts on model parametrisation and calib

Twenty-five years since foundational publications on valuing ecosystem services for human well-being1,2, addressing the global biodiversity crisis3 still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever4. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF)5 and the UN Sustainable Development Goals6, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature7. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change8, pandemic emergence9 and socio-environmental injustices10. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions7,11. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.

Twenty-five years since foundational publications on valuing ecosystem services for human well-being 1,2, addressing the global biodiversity crisis 3 still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever 4. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF) 5 and the UN Sustainable Development Goals 6, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature 7. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change 8, pandemic emergence 9 and socio-environmental injustices 10. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions 7,11. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.

Despite their impressive diversity and ecosystem relevance, insects are undervalued and rarely considered in conservation efforts, except for those that are medically or economically important. In terms of funding and effort, insect conservation research lags far behind vertebrate research, hampering the development of methodologies to better understand their conservation needs. This taxonomic bias has a severe limitation in that it only gives moral consideration to our closest evolutionary relatives, excluding the vast majority of other life forms on our planet. In this regard, the Field Environmental Philosophy (FEP) methodology provides a platform for the development of interdisciplinary approaches to biocultural conservation that combine ecological research and environmental ethics. We integrated ecological research, education, and environmental ethics over the last 15 years through the FEP to promote and foster freshwater insect awareness, conservation, and value in the Magellanic sub-Antarctic ecoregion of southern Chile. The FEP practice has enabled us to reach a wide range of people and raise awareness for these under-appreciated co-inhabitants. This methodology also promotes educational practices that encourage direct encounters with the inhabitants, habitats, and life habits, making them “visible” once more. Our work aims to awaken appreciation and valuation of the small co-inhabitants with whom we share the planet by providing a platform of scientific training and thinking from the earliest stages of education, with a novel combination of disciplines aiming to reveal the intrinsic value of freshwater insects.

Antarctica and the sub-Antarctic islands include some of the world’s most extreme and pristine terrestrial habitats. While they are characterized by low biodiversity and terrestrial communities comprise small, often microscopic, non-charismatic species, they have become a focus of studies of adaptation and biological function in the face of multiple extreme environmental stresses (Convey and Biersma 2023). Furthermore, they are highly sensitive to climate change and are considered natural laboratories to study and understand its impacts on biota (Contador et al. 2015; (Convey and Peck 2019). In the second half of the 20th century, the maritime Antarctic experienced considerable warming (Turner et al. 2014), causing deglaciation and the development of new ice-free areas and freshwater habitats, both along the coast and inland (Nędzarek and Pociecha 2010), a process that is expected to continue (Lee et al. 2017). While theregional warming trends paused in the early 21st century (Turner et al. 2016), they are predicted to resume through the rest of the century (Bracegirdle et al. 2020), and a recent botanical study from Signy Island (South Orkney Islands) suggests this may already be happening (Cannone et al. 2022).

Twenty-five years since foundational publications on valuing ecosystem services for human well-being 1,2, addressing the global biodiversity crisis 3 still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever 4. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF) 5 and the UN Sustainable Development Goals 6, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature 7. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change 8, pandemic emergence 9 and socio-environmental injustices 10. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions 7,11. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures.

The Cape Horn Biosphere Reserve, Chile, has been identified as a hotspot of bryophyte diversity and it has been suggested to be the same for lichens. However, in contrast to the extensive bryophyte studies, only preliminary lichen inventories had been conducted in this reserve. We conducted the first intensive study on the diversity of lichens on Navarino Island during the southern summers of 2005 and 2008. We explored the main habitat types of the island, including coastal areas, evergreen and deciduous forests, Magellanic tundra, and high Andean (“alpine”) habitats on the mountain summits. The following substrates on which lichens grow were considered: bark, wood (incl. logs, stumps), soil, mosses, and rocks. We recorded a total of 416 taxa, although some of them not identified to species level. A main result is the finding of two species that are proposed as new: The lichen Candelariella magellanica, and the saprobic fungus Sclerococcum nothofagi that grows on the bark of trees of the genus Nothofagus. In addition, one species of lichenicolous fungus is recorded for the first time on Navarino Island: Tremella haematommatis. These results provide additional evidence about the great diversity of lichens that are conserved in the Cape Horn Biosphere Reserve.

The Cape Horn Biosphere Reserve, Chile, has been identified as a hotspot of bryophyte diversity and it has been suggested to be the same for lichens. However, in contrast to the extensive bryophyte studies, only preliminary lichen inventories had been conducted in this reserve. We conducted the first intensive study on the diversity of lichens on Navarino Island during the southern summers of 2005 and 2008. We explored the main habitat types of the island, including coastal areas, evergreen and deciduous forests, Magellanic tundra, and high Andean (“alpine”) habitats on the mountain summits. The following substrates on which lichens grow were considered: bark, wood (incl. logs, stumps), soil, mosses, and rocks. We recorded a total of 416 taxa, although some of them not identified to species level. A main result is the finding of two species that are proposed as new: The lichen Candelariella magellanica, and the saprobic fungus Sclerococcum nothofagi that grows on the bark of trees of the genus Nothofagus. In addition, one species of lichenicolous fungus is recorded for the first time on Navarino Island: Tremella haematommatis. These results provide additional evidence about the great diversity of lichens that are conserved in the Cape Horn Biosphere Reserve.

Aim: The homogenisation of historically isolated gene pools has been recognised as one of the most serious conservation problems in the Antarctic. Lichens are the dominant components of terrestrial biotas in the Antarctic and in high mountain ranges of southern South America. We study the effects of dispersal strategy and migration history on their genetic structure to better understand the importance of these processes and their interplay in shaping population structure as well as their relevance for conservation. Location: Maritime Antarctic and southern South America. Methods: Populations of three fruticose lichen species, Usnea aurantiacoatra, U. antarctica and Cetraria aculeata, were collected in different localities in the Maritime Antarctic and southern South America. Usnea aurantiacoatra reproduces sexually by ascospores, whereas the other two species mostly disperse asexually by symbiotic diaspores. Samples were genotyped at 8–22 microsatellite loci. Different diversity and variance metrics, Bayesian cluster analyses and Discriminant Analysis of Principal Components (DAPC) were used to study population genetic structure. Historical migration patterns between southern South America and the Antarctic were investigated for U. aurantiacoatra and C. aculeata by approximate Bayesian computation (ABC). Results: The two vegetative species display lower levels of genetic diversity than U. aurantiacoatra. Antarctic populations of C. aculeata and South American populations of U. aurantiacoatra display much stronger genetic differentiation than their respective counterparts on the opposite side of the Drake Passage. Usnea antarctica was not found in South America but shows comparably low levels of genetic differentiation in Antarctica as those revealed for U. aurantiacoatra. Phylogeographic histories of lichens in the region differ strongly with recent colonisation in some instances and potential in situ persistence during Last Glacial Maximum (LGM) in others. Patte

Aim: The homogenisation of historically isolated gene pools has been recognised as one of the most serious conservation problems in the Antarctic. Lichens are the dominant components of terrestrial biotas in the Antarctic and in high mountain ranges of southern South America. We study the effects of dispersal strategy and migration history on their genetic structure to better understand the importance of these processes and their interplay in shaping population structure as well as their relevance for conservation. Location: Maritime Antarctic and southern South America. Methods: Populations of three fruticose lichen species, Usnea aurantiacoatra, U. antarctica and Cetraria aculeata, were collected in different localities in the Maritime Antarctic and southern South America. Usnea aurantiacoatra reproduces sexually by ascospores, whereas the other two species mostly disperse asexually by symbiotic diaspores. Samples were genotyped at 8–22 microsatellite loci. Different diversity and variance metrics, Bayesian cluster analyses and Discriminant Analysis of Principal Components (DAPC) were used to study population genetic structure. Historical migration patterns between southern South America and the Antarctic were investigated for U. aurantiacoatra and C. aculeata by approximate Bayesian computation (ABC). Results: The two vegetative species display lower levels of genetic diversity than U. aurantiacoatra. Antarctic populations of C. aculeata and South American populations of U. aurantiacoatra display much stronger genetic differentiation than their respective counterparts on the opposite side of the Drake Passage. Usnea antarctica was not found in South America but shows comparably low levels of genetic differentiation in Antarctica as those revealed for U. aurantiacoatra. Phylogeographic histories of lichens in the region differ strongly with recent colonisation in some instances and potential in situ persistence during Last Glacial Maximum (LGM) in others. Patte

The Yendegaia National Park, located to the south of Tierra del Fuego and at the eastern margin of the Darwin Mountain Range, forms part of the Cape Horn Biosphere Reserve (CHBR) and lies in the Magellanic sub-Antarctic ecoregion. This national park in the extreme south of Chile comprises an extensive valley surrounded by mountain ranges that give rise to glacial and rain or snow-melt streams. The present study provides the first inventory of freshwater macroinvertebrates within the park, further comparing the species composition of three rivers with contrasting riparian vegetation. One river has a riparian vegetation dominated by Coihüe de Magallanes (Nothofagus betuloides), an evergreen species. The river with riparian vegetation dominated by lenga presented a significantly higher diversity of macroinvertebrates than in the rivers with riparian vegetation dominated by ñirre and coihüe. The community composition of macroinvertebrates presents some affinities with that reported for other areas within the reserve with similar vegetational composition, such as Navarino Island or the Alberto de Agostini National Park. The influence of riparian vegetation and other environmental variables must be studied through other approaches. In this way, the need for studies that complement the inventory presented here emerges, contributing to a characterization that allows the evaluation of ecological patterns of aquatic macroinvertebrates. In this way, it will be possible to identify generalities and singularities of the freshwater biological communities and their environmental relationships in the southern tip of Chile.

The Diego Ramírez and Cape Horn archipelagos are located at the southern end of the Magellanic subantarctic ecoregion. The fauna of insects and other terrestrial invertebrates has been poorly characterized. In this work, we present an updated assessment of invertebrates, with a focus on the terrestrial entomofauna of the Diego Ramírez Archipelago. We reviewed biogeographic affinities of this southern archipelago with the rest of the subantarctic islands. We found that Gonzalo Island in the Diego Ramírez Archipelago is free of insect species and other exotic invertebrates. The island’s terrestrial invertebrate fauna registered during this study includes 32 taxa, mainly from the Class Insecta, which are distributed in different habitats, being the communities of Poa flabellata the most important habitats. The entomofauna of the Diego Ramírez Archipelago shows a low total similarity between the fauna reported and the rest of the islands, except with South Georgia. However, the biota that links them is of Gondwanic origin, which suggests the existence of ancient vicariant biogeographic connections. This work is a contribution to the development, strengthening and inauguration of the Cape Horn Long-Term Ecological Monitoring Network (LTER Cape Horn Network). The particular focus on the Diego Ramírez Islands contributes directly to filling a “blind spot” in our current knowledge of the effects of global environmental change in sub-Antarctic ecosystems, generating information essential to their conservation in the short, medium and long term.

Parts of Antarctica were amongst the most rapidly changing regions of the planet during the second half of the Twentieth Century. Even so, today, most of Antarctica remains in the grip of continental ice sheets, with only about 0.2% of its overall area being ice-free. The continent’s terrestrial fauna consists only of invertebrates, with just two native species of insects, the chironomid midges Parochlus steinenii and Belgica antarctica. We integrate ecophysiological information with the development of new high-resolution climatic layers for Antarctica, to better understand how the distribution of P. steinenii may respond to change over the next century under different IPCC climate change scenarios. We conclude that the species has the potential to expand its distribution to include parts of the west and east coasts of the Antarctic Peninsula and even coastal ice-free areas in parts of continental Antarctica. We propose P. steinenii as an effective native sentinel and indicator species of climate change in the Antarctic.

The Yendegaia National Park, located to the south of Tierra del Fuego and at the eastern margin of the Darwin Mountain Range, forms part of the Cape Horn Biosphere Reserve (CHBR) and lies in the Magellanic sub-Antarctic ecoregion. This national park in the extreme south of Chile comprises an extensive valley surrounded by mountain ranges that give rise to glacial and rain or snow-melt streams. The present study provides the first inventory of freshwater macroinvertebrates within the park, further comparing the species composition of three rivers with contrasting riparian vegetation. One river has a riparian vegetation dominated by Coihüe de Magallanes (Nothofagus betuloides), an evergreen species. The river with riparian vegetation dominated by lenga presented a significantly higher diversity of macroinvertebrates than in the rivers with riparian vegetation dominated by ñirre and coihüe. The community composition of macroinvertebrates presents some affinities with that reported for other areas within the reserve with similar vegetational composition, such as Navarino Island or the Alberto de Agostini National Park. The influence of riparian vegetation and other environmental variables must be studied through other approaches. In this way, the need for studies that complement the inventory presented here emerges, contributing to a characterization that allows the evaluation of ecological patterns of aquatic macroinvertebrates. In this way, it will be possible to identify generalities and singularities of the freshwater biological communities and their environmental relationships in the southern tip of Chile.

Parts of Antarctica were amongst the most rapidly changing regions of the planet during the second half of the Twentieth Century. Even so, today, most of Antarctica remains in the grip of continental ice sheets, with only about 0.2% of its overall area being ice-free. The continent’s terrestrial fauna consists only of invertebrates, with just two native species of insects, the chironomid midges Parochlus steinenii and Belgica antarctica. We integrate ecophysiological information with the development of new high-resolution climatic layers for Antarctica, to better understand how the distribution of P. steinenii may respond to change over the next century under different IPCC climate change scenarios. We conclude that the species has the potential to expand its distribution to include parts of the west and east coasts of the Antarctic Peninsula and even coastal ice-free areas in parts of continental Antarctica. We propose P. steinenii as an effective native sentinel and indicator species of climate change in the Antarctic.

The Diego Ramírez and Cape Horn archipelagos are located at the southern end of the Magellanic subantarctic ecoregion. The fauna of insects and other terrestrial invertebrates has been poorly characterized. In this work, we present an updated assessment of invertebrates, with a focus on the terrestrial entomofauna of the Diego Ramírez Archipelago. We reviewed biogeographic affinities of this southern archipelago with the rest of the subantarctic islands. We found that Gonzalo Island in the Diego Ramírez Archipelago is free of insect species and other exotic invertebrates. The island’s terrestrial invertebrate fauna registered during this study includes 32 taxa, mainly from the Class Insecta, which are distributed in different habitats, being the communities of Poa flabellata the most important habitats. The entomofauna of the Diego Ramírez Archipelago shows a low total similarity between the fauna reported and the rest of the islands, except with South Georgia. However, the biota that links them is of Gondwanic origin, which suggests the existence of ancient vicariant biogeographic connections. This work is a contribution to the development, strengthening and inauguration of the Cape Horn Long-Term Ecological Monitoring Network (LTER Cape Horn Network). The particular focus on the Diego Ramírez Islands contributes directly to filling a “blind spot” in our current knowledge of the effects of global environmental change in sub-Antarctic ecosystems, generating information essential to their conservation in the short, medium and long term.

Background. The study of altitudinal gradients provides insights about species diversity, distribution patterns and related drivers. The Magellanic sub-Antarctic ecoregion has a steep elevational gradient, peaking at around 1,000 m a.s.l., and marked changes in temperature and landscape composition can be observed over relatively short distances. Methods. This study assessed freshwater macroinvertebrate diversity associated with lakes and ponds along the altitudinal gradient of a Magellanic sub-Antarctic watershed. Results. A monotonic decline in species richness was observed with increasing elevation, with simpler and more even community composition at higher altitude. This pattern differs from the mid-peak trend found in streams of the same watershed. Functional feeding group structure also diminished with increasing elevation. Discussion. The study provides a descriptive baseline of macroinvertebrate community structure associated with lentic freshwater ecosystems in the Magellanic sub-Antarctic ecoregion, and confirms that elevation has substantial effects on community structure, function and environmental features, even in these relatively low elevation mountain ranges. The harsh environmental conditions of this ecoregion increase freshwater macroinvertebrate development time, as well as decreasing habitat availability and food supply, supporting simple but well adapted communities. In conjunction with previous research, this study provides a watershed-scale platform of information underpinning future long-term research in the region.

Background. The study of altitudinal gradients provides insights about species diversity, distribution patterns and related drivers. The Magellanic sub-Antarctic ecoregion has a steep elevational gradient, peaking at around 1,000 m a.s.l., and marked changes in temperature and landscape composition can be observed over relatively short distances. Methods. This study assessed freshwater macroinvertebrate diversity associated with lakes and ponds along the altitudinal gradient of a Magellanic sub-Antarctic watershed. Results. A monotonic decline in species richness was observed with increasing elevation, with simpler and more even community composition at higher altitude. This pattern differs from the mid-peak trend found in streams of the same watershed. Functional feeding group structure also diminished with increasing elevation. Discussion. The study provides a descriptive baseline of macroinvertebrate community structure associated with lentic freshwater ecosystems in the Magellanic sub-Antarctic ecoregion, and confirms that elevation has substantial effects on community structure, function and environmental features, even in these relatively low elevation mountain ranges. The harsh environmental conditions of this ecoregion increase freshwater macroinvertebrate development time, as well as decreasing habitat availability and food supply, supporting simple but well adapted communities. In conjunction with previous research, this study provides a watershed-scale platform of information underpinning future long-term research in the region.

PREMISE OF THE STUDY: American bipolar plant distributions characterize taxa at various taxonomic ranks but are most common in the bryophytes at infraspecific and infrageneric levels. A previous study on the bipolar disjunction in the dung moss genus Tetraplodon found that direct long-distance dispersal from North to South in the Miocene–Pleistocene accounted for the origin of the Southern American endemic Tetraplodon fuegianus, congruent with other molecular studies on bipolar bryophytes. The previous study, however, remained inconclusive regarding a specific northern hemisphere source region for the transequatorial dispersal event that gave rise to T. fuegianus. METHODS: To estimate spatial genetic structure and phylogeographic relationships within the bipolar lineage of Tetraplodon, which includes T. fuegianus, we analyzed thousands of restriction-site-associated DNA (RADseq) loci and single nucleotide polymorphisms using Bayesian individual assignment and maximum likelihood and coalescent model based phylogenetic approaches. KEY RESULTS: Northwestern North America is the most likely source of the recent ancestor to T. fuegianus. CONCLUSIONS: Tetraplodon fuegianus, which marks the southernmost populations in the bipolar lineage of Tetraplodon, arose following a single long-distance dispersal event involving a T. mnioides lineage that is now rare in the northern hemisphere and potentially restricted to the Pacific Northwest of North America. Furthermore, gene flow between sympatric lineages of Tetraplodon mnioides in the northern hemisphere is limited, possibly due to high rates of selfing or reproductive isolation.

The majority of plant species are glycophytes and are not salt-tolerant and maintain low sodium levels within their tissues; if. high tissue sodium concentrations do occur, it is in response to elevated environmental salt levels. Here we report an apparently novel and taxonomically diverse grouping of plants that continuously maintain high tissue sodium contents and share the rare feature of possessing symbiotic cyanobacteria. Leaves of Gunnera magellanica in Tierra del Fuego always had sodium contents (dry weight basis) of around 4.26 g kg?1, about 20 times greater than measured in other higher plants in the community (0.29 g kg?1). Potassium and chloride levels were also elevated. This was not a response to soil sodium and chloride levels as these were low at all sites. High sodium contents were also confirmed in G. magellanica from several other sites in Tierra del Fuego, in plants taken to, and cultivated in Madrid for 2 years at low soil salt conditions, and also in other free living or cultivated species of Gunnera from the UK and New Zealand. Gunnera species are the only angiosperms that possess cyanobacterial symbionts so we analysed other plants that have this rather rare symbiosis, all being glycophytes. Samples of Azolla, a floating aquatic fern, from Europe and New Zealand all had even higher sodium levels than Gunnera. Roots of the gymnosperm Cycas revoluta had lower sodium contents (2.52 ± 0.34 g kg?1) but still higher than the non-symbiotic glycophytes. The overaccumulation of salt even when it is at low levels in the environment appears to be linked to the possession of a cyanobacterial symbiosis although the actual functional basis is unclear.

The majority of plant species are glycophytes and are not salt-tolerant and maintain low sodium levels within their tissues; if. high tissue sodium concentrations do occur, it is in response to elevated environmental salt levels. Here we report an apparently novel and taxonomically diverse grouping of plants that continuously maintain high tissue sodium contents and share the rare feature of possessing symbiotic cyanobacteria. Leaves of Gunnera magellanica in Tierra del Fuego always had sodium contents (dry weight basis) of around 4.26 g kg?1, about 20 times greater than measured in other higher plants in the community (0.29 g kg?1). Potassium and chloride levels were also elevated. This was not a response to soil sodium and chloride levels as these were low at all sites. High sodium contents were also confirmed in G. magellanica from several other sites in Tierra del Fuego, in plants taken to, and cultivated in Madrid for 2 years at low soil salt conditions, and also in other free living or cultivated species of Gunnera from the UK and New Zealand. Gunnera species are the only angiosperms that possess cyanobacterial symbionts so we analysed other plants that have this rather rare symbiosis, all being glycophytes. Samples of Azolla, a floating aquatic fern, from Europe and New Zealand all had even higher sodium levels than Gunnera. Roots of the gymnosperm Cycas revoluta had lower sodium contents (2.52 ± 0.34 g kg?1) but still higher than the non-symbiotic glycophytes. The overaccumulation of salt even when it is at low levels in the environment appears to be linked to the possession of a cyanobacterial symbiosis although the actual functional basis is unclear.

PREMISE OF THE STUDY: American bipolar plant distributions characterize taxa at various taxonomic ranks but are most common in the bryophytes at infraspecific and infrageneric levels. A previous study on the bipolar disjunction in the dung moss genus Tetraplodon found that direct long-distance dispersal from North to South in the Miocene–Pleistocene accounted for the origin of the Southern American endemic Tetraplodon fuegianus, congruent with other molecular studies on bipolar bryophytes. The previous study, however, remained inconclusive regarding a specific northern hemisphere source region for the transequatorial dispersal event that gave rise to T. fuegianus. METHODS: To estimate spatial genetic structure and phylogeographic relationships within the bipolar lineage of Tetraplodon, which includes T. fuegianus, we analyzed thousands of restriction-site-associated DNA (RADseq) loci and single nucleotide polymorphisms using Bayesian individual assignment and maximum likelihood and coalescent model based phylogenetic approaches. KEY RESULTS: Northwestern North America is the most likely source of the recent ancestor to T. fuegianus. CONCLUSIONS: Tetraplodon fuegianus, which marks the southernmost populations in the bipolar lineage of Tetraplodon, arose following a single long-distance dispersal event involving a T. mnioides lineage that is now rare in the northern hemisphere and potentially restricted to the Pacific Northwest of North America. Furthermore, gene flow between sympatric lineages of Tetraplodon mnioides in the northern hemisphere is limited, possibly due to high rates of selfing or reproductive isolation.

The external morphometrics of shell and radula morphology were performed in two species of micromollusks of the genus Eatoniella in Navarino Island, Chile. A total of 50 specimens of E. picea and 72 of E. nigra were analyzed. These species have similar morphology, but E. picea has a smaller diameter/length ratio (0.53 ± 0.02) than E. nigra (0.61 ± 0.04). In relation to the radula morphology, E. picea has wider middle cuspid teeth and small denticles in its border, meanwhile E. nigra has pointed central cuspid teeth.

Following the retreat of a glacier, microbial colonization paves the way for future plant successions as nutrients are gradually introduced into the ecosystem. Characterizing the dynamics of this initial microbial colonization process is a key to understanding how these rapidly receding glacier areas are colonized. This study examines primary successions of bacteria, fungi and algae in two glacier forefields chronosequences on opposite slopes of Cordillera Darwin (Tierra del Fuego, Chile). Both slopes (southern and northern) show contrasting climate factors along with rapid rates of plant succession. Through a high-throughput sequencing approach, we identified Cyanobacteria as the dominant bacteria in younger soils close to the glacier terminus, whereas abundances of Alphaproteobacteria and Acidobacteria increased with soil surface age. Lichen-forming fungi and parasitic fungi were the most abundant fungal groups in younger succession stages, while saprophytic and mycorrhizal orders dominated later stages. The order Prasiolales predominated algal communities close to the glacier terminus, while Microthamniales and Chlamydomonadales orders dominated subsequent succession stages. Our observations reflect a changing community structure over time of the three microbial groups examined, and the replacement of taxa during the succession. Changes in composition are especially marked between the youngest succession states and subsequent ones in both forefields. Simultaneous analysis of bacterial, fungal and algal communities revealed the different trajectories of the three groups, with bacterial and fungal communities showing more marked succession patterns. Our results point to more relevant roles for bacteria at the initial stages of succession, while fungi could play a dominant role over bacteria as succession progresses. The ubiquity of algal taxa along the chronosequences was also observed. The two glacier forefields showed different microbial temporal dynamics, indica

A previously established chronosequence from Pia Glacier forefield in Tierra del Fuego (Chile) containing soils of different ages (from bare soils to forest ones) is analyzed. We used this chronosequence as framework to postulate that microbial successional development would be accompanied by changes in functionality. To test this, the GeoChip functional microarray was used to identify diversity of genes involved in microbial carbon and nitrogen metabolism, as well as other genes related to microbial stress response and biotic interactions. Changes in putative functionality generally reflected succession-related taxonomic composition of soil microbiota. Major shifts in carbon fixation and catabolism were observed, as well as major changes in nitrogen metabolism. At initial microbial dominated succession stages, microorganisms could be mainly involved in pathways that help to increase nutrient availability, while more complex microbial transformations such as denitrification and methanogenesis, and later degradation of complex organic substrates, could be more prevalent at vegetated successional states. Shifts in virus populations broadly reflected changes in microbial diversity. Conversely, stress response pathways appeared relatively well conserved for communities along the entire chronosequence. We conclude that nutrient utilization is likely the major driver of microbial succession in these soils. [Int Microbiol 19(3):161-173 (2016)]Keywords: Functional genes · antibiotic resistance · GeoChip microarray · primary succession · chronosequence

The International Long-Term Ecological Research (ILTER) network comprises > 600 scientific groups conducting site-based research within 40 countries. Its mission includes improving the understanding of global ecosystems and informs solutions to current and future environmental problems at the global scales. The ILTER network covers a wide range of social-ecological conditions and is aligned with the Programme on Ecosystem Change and Society (PECS) goals and approach. Our aim is to examine and develop the conceptual basis for proposed collaboration between ILTER and PECS. We describe how a coordinated effort of several contrasting LTER site-based research groups contributes to the understanding of how policies and technologies drive either toward or away from the sustainable delivery of ecosystem services. This effort is based on three tenets: transdisciplinary research; cross-scale interactions and subsequent dynamics; and an ecological stewardship orientation. The overarching goal is to design management practices taking into account trade-offs between using and conserving ecosystems toward more sustainable solutions. To that end, we propose a conceptual approach linking ecosystem integrity, ecosystem services, and stakeholder well-being, and as a way to analyze trade-offs among ecosystem services inherent in diverse management options. We also outline our methodological approach that includes: (i) monitoring and synthesis activities following spatial and temporal trends and changes on each site and by documenting cross-scale interactions; (ii) developing analytical tools for integration; (iii) promoting trans-site comparison; and (iv) developing conceptual tools to design adequate policies and management interventions to deal with trade-offs. Finally, we highlight the heterogeneity in the social-ecological setting encountered in a subset of 15 ILTER sites. These study cases are diverse enough to provide a broad cross-section of contrasting ecosystems with differen

The International Long-Term Ecological Research (ILTER) network comprises > 600 scientific groups conducting site-based research within 40 countries. Its mission includes improving the understanding of global ecosystems and informs solutions to current and future environmental problems at the global scales. The ILTER network covers a wide range of social-ecological conditions and is aligned with the Programme on Ecosystem Change and Society (PECS) goals and approach. Our aim is to examine and develop the conceptual basis for proposed collaboration between ILTER and PECS. We describe how a coordinated effort of several contrasting LTER site-based research groups contributes to the understanding of how policies and technologies drive either toward or away from the sustainable delivery of ecosystem services. This effort is based on three tenets: transdisciplinary research; cross-scale interactions and subsequent dynamics; and an ecological stewardship orientation. The overarching goal is to design management practices taking into account trade-offs between using and conserving ecosystems toward more sustainable solutions. To that end, we propose a conceptual approach linking ecosystem integrity, ecosystem services, and stakeholder well-being, and as a way to analyze trade-offs among ecosystem services inherent in diverse management options. We also outline our methodological approach that includes: (i) monitoring and synthesis activities following spatial and temporal trends and changes on each site and by documenting cross-scale interactions; (ii) developing analytical tools for integration; (iii) promoting trans-site comparison; and (iv) developing conceptual tools to design adequate policies and management interventions to deal with trade-offs. Finally, we highlight the heterogeneity in the social-ecological setting encountered in a subset of 15 ILTER sites. These study cases are diverse enough to provide a broad cross-section of contrasting ecosystems with differen

A previously established chronosequence from Pia Glacier forefield in Tierra del Fuego (Chile) containing soils of different ages (from bare soils to forest ones) is analyzed. We used this chronosequence as framework to postulate that microbial successional development would be accompanied by changes in functionality. To test this, the GeoChip functional microarray was used to identify diversity of genes involved in microbial carbon and nitrogen metabolism, as well as other genes related to microbial stress response and biotic interactions. Changes in putative functionality generally reflected succession-related taxonomic composition of soil microbiota. Major shifts in carbon fixation and catabolism were observed, as well as major changes in nitrogen metabolism. At initial microbial dominated succession stages, microorganisms could be mainly involved in pathways that help to increase nutrient availability, while more complex microbial transformations such as denitrification and methanogenesis, and later degradation of complex organic substrates, could play more important roles at vegetated successional states. Shifts in virus populations broadly reflected changes in microbial diversity. Conversely, stress response pathways appeared relatively well conserved for communities along the entire chronosequence. We conclude nutrient utilization is likely the major driver of microbial succession in these soils.

Chilean sub-Antarctic Channels region is one of the most diverse regions in molluscs species of the South Pacific Ocean in South America. This region exhibit intertidal zones with a high environmental heterogeneity at a local scale, including seasonal changes in photoperiod, rocky substrate diversity, salinity and temperature gradients. This study characterized molluscs assemblages in Róbalo bay 54°55'S (Beagle Channel), identifying spatial-temporal changes in assemblage composition, species richness, abundance, functional groups, and diversity of molluscs species. We registered 34 species comprising 4 functional groups, being mobile herbivores the most diverse group (21 species). The most abundant molluscs were Mytilus edulis platensis and Perumytilus purpuratus. Considering the mobile species only, the most abundant were Laevilitorina caliginosa and Siphonaria lessonii. In seasonal terms, species richness and abundance of mobile herbivores showed an increase during the austral summer. While the abundance of M. edulis platensis and mobile carnivores remained stable during the seasons. Regarding vertical zonation within the intertidal, we found that L. caliginosa is mainly associated with high intertidal, Pareuthria plumbea to the mid-zone, and N. deaurata to the low intertidal zone. Róbalo Bay high beta molluscs diversity was associated to the spatial variability of intertidal zones. These changes can be detected in between sites separated only by hundreds of meters, where local environmental heterogeneity likely plays a role structuring ecological assemblages and communities Sub-Antarctic channels., Los canales subantárticos de Chile son una de las regiones con mayor diversidad de moluscos del océano Pacífico en el sur de Sudamérica. Esta región presenta extensas zonas intermareales sujetas a una marcada estacionalidad con cambios en el fotoperiodo y una alta heterogeneidad ambiental, que incluye diversidad de sustratos, gradientes de salinidad y temperatura. El presente estudio caracterizó el ensamble de moluscos de bahía Róbalo 54°55'S (canal Beagle) y evaluó los cambios espacio-estacionales de la composición, riqueza y diversidad de moluscos. Se registraron 34 especies de moluscos, y se caracterizaron 4 grupos funcionales, siendo el más diverso los herbívoros móviles (21 especies). Los moluscos más abundantes fueron los filtradores sésiles, Mytilus edulis platensis y Perumytilus purpuratus. Las especies móviles más abundantes fueron Laevilitorina caliginosa y Siphonaria lessonii. En términos estacionales, la riqueza de especies y abundancia de los herbívoros móviles presentaron un aumento durante el verano austral. Mientras que la abundancia de M. edulis platensis y los carnívoros móviles se mantuvieron estables durante las estaciones. Respecto a la zonificación vertical dentro del intermareal, se encontró que L. caliginosa está asociada principalmente al intermareal alto, Pareuthria plumbea a la zona media y N. deaurata al intermareal bajo. En bahía Róbalo se registró una alta diversidad beta de moluscos, asociada a la variabilidad espacial de las zonas intermareales. Estos cambios se pueden detectar entre sitios separados por centenas de metros, donde la heterogeneidad ambiental local probablemente juega un rol ecológico en la estructuración de ensambles y comunidades en canales subantárticos.

Sphagnum-dominated peat bogs that are strongly embedded within the southern temperate forest matrix are increasingly being used for agriculture. Nevertheless, little is known about their biodiversity. Moreover, the remote areas of southern Chile where peat bogs are found, such as the Cape Horn Biosphere Reserve (CHBR, 54-55ºS), where birds are the most diverse and best represented group of vertebrates, have not been well-investigated. With the aim to broaden this knowledge in the CHBR, we studied the diversity of the avian assemblage in peat bogs on Navarino Island. We compared the composition of avian species between wetlands with and without peat bogs to test if Sphagnum bogs represented a singular habitat for birds in this area. Furthermore, the 37 bird species recorded in these habitats were classifed according to guild structure. The community similarity values showed that peat bogs hosted a bird composition that was different from that present in wetlands without Sphagnum, suggesting that peat bogs are a singular type of habitat for birds in the CHBR. The most frequently feeding groups recorded in these wetlands were insectivores (48.7%), followed by omnivores (23.1%). Our results showed that, in contrast to previous studies of birds in peat bogs, these environments constituted a distinct wetland habitat for feeding, reproduction and sheltering for some species in the CHBR. Thus, plans for the conservation and rational use of peat ecosystems should consider the high value of these habitats for biodiversity on a landscape scale, especially for birds of the southernmost extreme of the Americas., Las turberas esfagnosas que se encuentran fuertemente embebidas en la matriz de bosques templados australes, se utilizan de forma creciente en agricultura. Sin embargo, el conocimiento de su biodiversidad es escaso. Más aún, zonas remotas del sur de Chile donde se encuentran las turberas, como la Reserva de Biosfera Cabo de Hornos (RBCH, 54-55º S), donde las aves constituyen el grupo de vertebrados más diverso y representativo, aún han sido escasamente estudiadas. Con el objetivo de aportar en su conocimiento en la RBCH, se estudió la diversidad del ensamble de aves en turberas esfagnosas de la isla Navarino. Se exploró si su composición específca es igual al de los humedales sin turbera, probando si las turberas constituyen o no un hábitat singular para las aves. También se clasifcó a las 37 especies de aves registradas en estos hábitats de acuerdo a la estructura de gremios. Los valores de similitud taxocenótica señalaron que la composición de aquellos con turbera difrió de aquellos sin turbera, sugiriendo que este hábitat es singular para las aves. El tipo de alimentación más frecuente fue la insectivoría (48,7%), seguido por la omnivoría (23,1%). Los resultados muestran que, a diferencia de lo señalado en trabajos previos sobre aves de turberas, estos ambientes constituyen un humedal-hábitat singular para la alimentación, reproducción y refugio de algunas especies en la RBCH. De esta manera, la conservación y uso racional de turberas debe considerar el valor que tienen como hábitat para la biodiversidad a escala de paisaje, especialmente para las aves del extremo sur americano.

Sphagnum-dominated peat bogs that are strongly embedded within the southern temperate forest matrix are increasingly being used for agriculture. Nevertheless, little is known about their biodiversity. Moreover, the remote areas of southern Chile where peat bogs are found, such as the Cape Horn Biosphere Reserve (CHBR, 54-55ºS), where birds are the most diverse and best represented group of vertebrates, have not been well-investigated. With the aim to broaden this knowledge in the CHBR, we studied the diversity of the avian assemblage in peat bogs on Navarino Island. We compared the composition of avian species between wetlands with and without peat bogs to test if Sphagnum bogs represented a singular habitat for birds in this area. Furthermore, the 37 bird species recorded in these habitats were classifed according to guild structure. The community similarity values showed that peat bogs hosted a bird composition that was different from that present in wetlands without Sphagnum, suggesting that peat bogs are a singular type of habitat for birds in the CHBR. The most frequently feeding groups recorded in these wetlands were insectivores (48.7%), followed by omnivores (23.1%). Our results showed that, in contrast to previous studies of birds in peat bogs, these environments constituted a distinct wetland habitat for feeding, reproduction and sheltering for some species in the CHBR. Thus, plans for the conservation and rational use of peat ecosystems should consider the high value of these habitats for biodiversity on a landscape scale, especially for birds of the southernmost extreme of the Americas., Las turberas esfagnosas que se encuentran fuertemente embebidas en la matriz de bosques templados australes, se utilizan de forma creciente en agricultura. Sin embargo, el conocimiento de su biodiversidad es escaso. Más aún, zonas remotas del sur de Chile donde se encuentran las turberas, como la Reserva de Biosfera Cabo de Hornos (RBCH, 54-55º S), donde las aves constituyen el grupo de vertebrados más diverso y representativo, aún han sido escasamente estudiadas. Con el objetivo de aportar en su conocimiento en la RBCH, se estudió la diversidad del ensamble de aves en turberas esfagnosas de la isla Navarino. Se exploró si su composición específca es igual al de los humedales sin turbera, probando si las turberas constituyen o no un hábitat singular para las aves. También se clasifcó a las 37 especies de aves registradas en estos hábitats de acuerdo a la estructura de gremios. Los valores de similitud taxocenótica señalaron que la composición de aquellos con turbera difrió de aquellos sin turbera, sugiriendo que este hábitat es singular para las aves. El tipo de alimentación más frecuente fue la insectivoría (48,7%), seguido por la omnivoría (23,1%). Los resultados muestran que, a diferencia de lo señalado en trabajos previos sobre aves de turberas, estos ambientes constituyen un humedal-hábitat singular para la alimentación, reproducción y refugio de algunas especies en la RBCH. De esta manera, la conservación y uso racional de turberas debe considerar el valor que tienen como hábitat para la biodiversidad a escala de paisaje, especialmente para las aves del extremo sur americano.

The American mink, originally from North America, is an invasive species of high conservation concern. It is currently in its initial phase of invasion on Navarino Island in southern Chile. This dissertation aims at broadening the basic knowledge of the ecology and impacts of the mink for decision-making for its management. The investigation includes the determination of relative abundance and habitat preferences of mink, its diet, impacts on the nest survival of ground-nesting waterbirds, as well as public perceptions and acceptance of control measurements. The results provide managers with a list of particularly vulnerable bird species and practical recommendations from an integrative conservation perspective., Der aus Nordamerika stammende Amerikanische Mink ist eine invasive Art mit hoher Naturschutzrelevanz. Er befindet sich in der Anfangsphase seiner Etablierung auf der südchilenischen Insel Navarino. Ziel der Dissertation ist es, das Grundlagenwissen über die Ökologie und die Auswirkungen des Minks für Entscheidungsfindungen zu dessen Management zu erweitern. Die Untersuchungen beziehen sich auf die relative Abundanz und Habitatvorlieben des Minks, sein Beutespektrum, die Auswirkungen auf den Nisterfolg bodenbrütender Küstenvögel, sowie die öffentliche Wahrnehmung und Akzeptanz von Kontrollmaßnahmen. Aus den Ergebnissen werden besonders gefährdete Vogelarten bestimmt und praktische Empfehlungen für einen integrativen Naturschutz erarbeitet.

The American mink, originally from North America, is an invasive species of high conservation concern. It is currently in its initial phase of invasion on Navarino Island in southern Chile. This dissertation aims at broadening the basic knowledge of the ecology and impacts of the mink for decision-making for its management. The investigation includes the determination of relative abundance and habitat preferences of mink, its diet, impacts on the nest survival of ground-nesting waterbirds, as well as public perceptions and acceptance of control measurements. The results provide managers with a list of particularly vulnerable bird species and practical recommendations from an integrative conservation perspective., Der aus Nordamerika stammende Amerikanische Mink ist eine invasive Art mit hoher Naturschutzrelevanz. Er befindet sich in der Anfangsphase seiner Etablierung auf der südchilenischen Insel Navarino. Ziel der Dissertation ist es, das Grundlagenwissen über die Ökologie und die Auswirkungen des Minks für Entscheidungsfindungen zu dessen Management zu erweitern. Die Untersuchungen beziehen sich auf die relative Abundanz und Habitatvorlieben des Minks, sein Beutespektrum, die Auswirkungen auf den Nisterfolg bodenbrütender Küstenvögel, sowie die öffentliche Wahrnehmung und Akzeptanz von Kontrollmaßnahmen. Aus den Ergebnissen werden besonders gefährdete Vogelarten bestimmt und praktische Empfehlungen für einen integrativen Naturschutz erarbeitet.