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1.
Biol Lett ; 19(4): 20220578, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37073526

RESUMO

Understanding how species respond to different anthropogenic pressures is essential for conservation planning. The archaeological record has great potential to inform extinction risk assessment by providing evidence on past human-caused biodiversity loss, but identifying specific drivers of past declines from environmental archives has proved challenging. We used 17 684 Holocene zooarchaeological records for 15 European large mammal species together with data on past environmental conditions and anthropogenic activities across Europe, to assess the ability of environmental archives to determine the relative importance of different human pressures in shaping faunal distributions through time. Site occupancy probability showed differing significant relationships with environmental covariates for all species, and nine species also showed significant relationships with anthropogenic covariates (human population density, % cropland, % grazing land). Across-species differences in negative relationships with covariates provide ecological insights for understanding extinction dynamics: some mammals (red deer, aurochs, wolf, wildcat, lynx, pine marten and beech marten) were more vulnerable to past human-environmental interactions, and differing single and synergistic anthropogenic factors influenced likelihood of past occurrence across species. Our results provide new evidence for pre-industrial population fragmentation and depletion in European mammals, and demonstrate the usefulness of historical baselines for understanding species' varying long-term sensitivity to multiple threats.


Assuntos
Cervos , Extinção Biológica , Humanos , Animais , Biodiversidade , Densidade Demográfica , Mamíferos , Europa (Continente) , Ecossistema , Conservação dos Recursos Naturais
2.
Conserv Biol ; 37(3): e14043, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36756799

RESUMO

Many species are restricted to a marginal or suboptimal fraction of their historical range due to anthropogenic impacts, making it hard to interpret their ecological preferences from modern-day data alone. However, inferring past ecological states is limited by the availability of robust data and biases in historical archives, posing a challenge for policy makers . To highlight how historical records can be used to understand the ecological requirements of threatened species and inform conservation, we investigated sperm whale (Physeter macrocephalus) distribution in the Western Indian Ocean. We assessed differences in information content and habitat suitability predictions based on whale occurrence data from Yankee whaling logs (1792-1912) and from modern cetacean surveys (1995-2020). We built maximum entropy habitat suitability models containing static (bathymetry-derived) variables to compare models comprising historical-only and modern-only data. Using both historical and modern habitat suitability predictions  we assessed marine protected area (MPA) placement by contrasting suitability in- and outside MPAs. The historical model predicted high habitat suitability in shelf and coastal regions near continents and islands, whereas the modern model predicted a less coastal distribution with high habitat suitability more restricted to areas of steep topography. The proportion of high habitat suitability inside versus outside MPAs was higher when applying the historical predictions than the modern predictions, suggesting that different marine spatial planning optimums can be reached from either data sources. Moreover, differences in relative habitat suitability predictions between eras were consistent with the historical depletion of sperm whales from coastal regions, which were easily accessed and targeted by whalers, resulting in a modern distribution limited more to steep continental margins and remote oceanic ridges. The use of historical data can provide important new insights and, through cautious interpretation, inform conservation planning and policy, for example, by identifying refugee species and regions of anticipated population recovery.


Contrastes del contenido de información ecológica entre los archivos de la caza de ballenas y los censos actuales de cetáceos para la planeación de la conservación y la identificación de cambios en la distribución histórica Resumen Muchas especies están restringidas a una fracción marginal o subóptima de su área de distribución histórica debido a impactos antropogénicos. Esto dificulta interpretar sus preferencias ecológicas con sólo usar los datos actuales. Sin embargo, la inferencia de estados ecológicos pasados está limitada a la disponibilidad de datos sólidos y a los sesgos de los archivos históricos, lo que plantea un reto para la conservación y los responsables de las políticas. Analizamos la distribución del cachalote (Physeter macrocephalus) en el Océano Índico occidental para resaltar cómo pueden utilizarse los registros históricos para comprender los requisitos ecológicos de las especies amenazadas y direccionar su conservación. Evaluamos las diferencias en el contenido de la información y las predicciones de idoneidad del hábitat basadas en los datos de presencia de ballenas de los registros balleneros Yanquis (1792-1912) y de los estudios actuales sobre cetáceos (1995-2020). Construimos modelos de idoneidad de hábitat con máxima entropía que incluían variables estáticas (derivadas de la batimetría) para comparar los modelos que abarcan datos históricos y actuales. Evaluamos la ubicación de las áreas marinas protegidas (AMP) contrastando las predicciones dentro y fuera de ellas con los modelos históricos y actuales de la idoneidad del hábitat. El modelo histórico predijo una alta idoneidad del hábitat en las regiones costeras y de la plataforma continental cercanas a los continentes e islas, mientras que el modelo moderno predijo una distribución menos costera con una alta idoneidad del hábitat más restringida a las zonas de topografía escarpada. La proporción de hábitats de alta idoneidad dentro y fuera de las AMP fue mayor con la aplicación de las predicciones históricas que con la de las modernas, lo que sugiere que se pueden alcanzar diferentes niveles óptimos de ordenación del espacio marino a partir de ambas fuentes de datos. Además, las diferencias entre los periodos en las predicciones relacionadas con la idoneidad del hábitat fueron coherentes con la reducción histórica de los cachalotes en las regiones costeras, las cuales eran fácilmente accesibles para los balleneros, lo que resultó en una distribución actual más limitada a los márgenes continentales escarpados y a las crestas oceánicas remotas. El uso de datos históricos puede aportar nuevos e importantes conocimientos e informar, mediante una interpretación prudente, a la planificación y la política de conservación; por ejemplo, con la identificación de especies refugiadas y regiones de recuperación poblacional.


Assuntos
Conservação dos Recursos Naturais , Baleias , Animais , Conservação dos Recursos Naturais/métodos , Ecossistema , Espécies em Perigo de Extinção
3.
Mol Biol Evol ; 38(1): 84-95, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33035304

RESUMO

Reconstructing the evolutionary history of island biotas is complicated by unusual morphological evolution in insular environments. However, past human-caused extinctions limit the use of molecular analyses to determine origins and affinities of enigmatic island taxa. The Caribbean formerly contained a morphologically diverse assemblage of caviomorph rodents (33 species in 19 genera), ranging from ∼0.1 to 200 kg and traditionally classified into three higher-order taxa (Capromyidae/Capromyinae, Heteropsomyinae, and Heptaxodontidae). Few species survive today, and the evolutionary affinities of living and extinct Caribbean caviomorphs to each other and to mainland taxa are unclear: Are they monophyletic, polyphyletic, or paraphyletic? We use ancient DNA techniques to present the first genetic data for extinct heteropsomyines and heptaxodontids, as well as for several extinct capromyids, and demonstrate through analysis of mitogenomic and nuclear data sets that all sampled Caribbean caviomorphs represent a well-supported monophyletic group. The remarkable morphological and ecological variation observed across living and extinct caviomorphs from Cuba, Hispaniola, Jamaica, Puerto Rico, and other islands was generated through within-archipelago evolutionary radiation following a single Early Miocene overwater colonization. This evolutionary pattern contrasts with the origination of diversity in many other Caribbean groups. All living and extinct Caribbean caviomorphs comprise a single biologically remarkable subfamily (Capromyinae) within the morphologically conservative living Neotropical family Echimyidae. Caribbean caviomorphs represent an important new example of insular mammalian adaptive radiation, where taxa retaining "ancestral-type" characteristics coexisted alongside taxa occupying novel island niches. Diversification was associated with the greatest insular body mass increase recorded in rodents and possibly the greatest for any mammal lineage.


Assuntos
DNA Antigo/análise , Roedores/genética , Animais , Filogeografia , Índias Ocidentais
4.
Glob Chang Biol ; 28(23): 6847-6856, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36074067

RESUMO

Traditional Chinese medicine (TCM) is highlighted by conservation practitioners as an ongoing threat to many overharvested plant and animal species, including several charismatic threatened vertebrates. However, studies that provide evidence-based and practical recommendations on how to better regulate the TCM trade for sustainability and biodiversity conservation remain limited. China is the biggest promotor of and market for TCM and understanding the TCM trade in China is important for global biodiversity conservation. In particular, conservation researchers need to better understand how the TCM trade and its regulations interact with China's development needs and should collaborate with TCM communities to propose locally adapted suggestions to decision makers. However, progress in these areas has been restricted by language, cultural, and knowledge barriers. In this paper, we provide an overview of the current status of TCM-related regulations in China, identify weaknesses in regulation frameworks, and highlight issues that currently limit our understanding of the magnitude, dynamics, and impact of the trade. We propose changes in trade regulations, actions to enhance law enforcement, and future research directions to encourage a more sustainable TCM trade that benefits both global biodiversity conservation and TCM development.


Assuntos
Biodiversidade , Medicina Tradicional Chinesa , Animais , China , Plantas
5.
Biol Lett ; 18(4): 20220094, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35414222

RESUMO

Megafauna play a disproportionate role in developing and maintaining their biomes, by regulating plant dispersal, community structure and nutrient cycling. Understanding the ecological roles of extinct megafaunal communities, for example through dietary reconstruction using isotope analysis, is necessary to determine pre-human states and set evidence-based restoration goals. We use δ13C and δ15N isotopic analyses to reconstruct Holocene feeding guilds in Madagascar's extinct megaherbivores, which included elephant birds, hippopotami and giant tortoises that occurred across multiple habitats and elevations. We compare isotopic data from seven taxa and two elephant bird eggshell morphotypes against contemporary regional floral baselines to infer dietary subsistence strategies. Most taxa show high consumption of C3 and/or CAM plants, providing evidence of widespread browsing ecology. However, Aepyornis hildebrandti, an elephant bird restricted to the central highlands region, has isotope values with much higher δ13C values than other taxa. This species is interpreted as having obtained up to 48% of its diet from C4 grasses. These findings provide new evidence for distinct browsing and grazing guilds in Madagascar's Holocene megaherbivore fauna, with implications for past regional distribution of ecosystems dominated by endemic C4 grasses.


Assuntos
Aves , Ecossistema , Animais , Isótopos de Carbono/análise , Dieta , Fósseis , Humanos , Isótopos , Madagáscar , Plantas , Poaceae
6.
Proc Natl Acad Sci U S A ; 116(51): 25745-25755, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31772017

RESUMO

Venom systems are key adaptations that have evolved throughout the tree of life and typically facilitate predation or defense. Despite venoms being model systems for studying a variety of evolutionary and physiological processes, many taxonomic groups remain understudied, including venomous mammals. Within the order Eulipotyphla, multiple shrew species and solenodons have oral venom systems. Despite morphological variation of their delivery systems, it remains unclear whether venom represents the ancestral state in this group or is the result of multiple independent origins. We investigated the origin and evolution of venom in eulipotyphlans by characterizing the venom system of the endangered Hispaniolan solenodon (Solenodon paradoxus). We constructed a genome to underpin proteomic identifications of solenodon venom toxins, before undertaking evolutionary analyses of those constituents, and functional assessments of the secreted venom. Our findings show that solenodon venom consists of multiple paralogous kallikrein 1 (KLK1) serine proteases, which cause hypotensive effects in vivo, and seem likely to have evolved to facilitate vertebrate prey capture. Comparative analyses provide convincing evidence that the oral venom systems of solenodons and shrews have evolved convergently, with the 4 independent origins of venom in eulipotyphlans outnumbering all other venom origins in mammals. We find that KLK1s have been independently coopted into the venom of shrews and solenodons following their divergence during the late Cretaceous, suggesting that evolutionary constraints may be acting on these genes. Consequently, our findings represent a striking example of convergent molecular evolution and demonstrate that distinct structural backgrounds can yield equivalent functions.


Assuntos
Eutérios , Evolução Molecular , Genoma/genética , Musaranhos , Peçonhas/genética , Animais , Eutérios/classificação , Eutérios/genética , Eutérios/fisiologia , Duplicação Gênica , Masculino , Filogenia , Proteômica , Musaranhos/classificação , Musaranhos/genética , Musaranhos/fisiologia , Calicreínas Teciduais/genética
7.
J Environ Manage ; 310: 114716, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35184009

RESUMO

Conservation outreach is regularly conducted to increase support for conservation by altering local awareness and attitudes about species or environmental issues. However, there is often little assessment of the effectiveness of these activities. We investigated knowledge of past conservation outreach in 26 villages adjacent to Bawangling National Nature Reserve, Hainan, China, which contains the last population of the Hainan gibbon (Nomascus hainanus). The medium of past outreach activities was reported most frequently by interviewees, followed by who delivered them and the outreach topic, with the fewest interviewees reporting the specific messages being communicated (the consequences of following conservation management policies). Negatively-framed messages, emphasizing prohibited activities and associated punishments, were reported more than positively-framed messages that aimed to foster conservation support. Male interviewees and those with higher education levels reported more aspects of past activities. The Hainan gibbon had higher salience than other threatened native species, and reporting the occurrence (but not necessarily the content) of past outreach was associated with increased likelihood of knowing that gibbons were threatened. These findings highlight the need for conservation outreach to increase both exposure and retention of key messages among target audiences. Meaningful and concrete conservation benefits should be communicated to local communities, and the effectiveness of outreach using a flagship species could be expanded to also improve awareness of other conservation-priority species within the same landscape.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Animais , Atitude , China , Humanos , Hylobates , Conhecimento , Masculino
8.
Proc Biol Sci ; 288(1946): 20202905, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33715429

RESUMO

Preventing extinctions requires understanding macroecological patterns of vulnerability or persistence. However, correlates of risk can be nonlinear, within-species risk varies geographically, and current-day threats cannot reveal drivers of past losses. We investigated factors that regulated survival or extinction in Caribbean mammals, which have experienced the globally highest level of human-caused postglacial mammalian extinctions, and included all extinct and extant Holocene island populations of non-volant species (219 survivals or extinctions across 118 islands). Extinction selectivity shows a statistically detectable and complex body mass effect, with survival probability decreasing for both mass extremes, indicating that intermediate-sized species have been more resilient. A strong interaction between mass and age of first human arrival provides quantitative evidence of larger mammals going extinct on the earliest islands colonized, revealing an extinction filter caused by past human activities. Survival probability increases on islands with lower mean elevation (mostly small cays acting as offshore refugia) and decreases with more frequent hurricanes, highlighting the risk of extreme weather events and rising sea levels to surviving species on low-lying cays. These findings demonstrate the interplay between intrinsic biology, regional ecology and specific local threats, providing insights for understanding drivers of biodiversity loss across island systems and fragmented habitats worldwide.


Assuntos
Extinção Biológica , Mamíferos , Animais , Região do Caribe , Humanos , Ilhas , Índias Ocidentais
9.
Conserv Biol ; 35(5): 1598-1614, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33554359

RESUMO

The International Union for Conservation of Nature's Red List of Threatened Species (RLS) is the key global tool for objective, repeatable assessment of species' extinction risk status, and plays an essential role in tracking biodiversity loss and guiding conservation action. Satellite remote sensing (SRS) data sets on global ecosystem distributions and functioning show exciting potential for informing range-based RLS assessment, but their incorporation has been restricted by low temporal resolution and coverage of data sets, lack of incorporation of degradation-driven habitat loss, and noninclusion of assumptions related to identification of changing habitat distributions for taxa with varying habitat dependency and ecologies. For poorly known mangrove-associated Cuban hutias (Mesocapromys spp.), we tested the impact of possible assumptions regarding these issues on range-based RLS assessment outcomes. Specifically, we used annual (1985-2018) Landsat data and land-cover classification and habitat degradation analyses across different internal time series slices to simulate range-based RLS assessments for our case study taxa to explore potential assessment uncertainty arising from temporal SRS data set coverage, incorporating proxies of (change in) habitat quality, and assumptions on spatial scaling of habitat extent for RLS parameter generation. We found extensive variation in simulated species-specific range-based RLS assessments, and this variation was mostly associated with the time series over which parameters were estimated. However, results of some species-specific assessments differed by up to 3 categories (near threatened to critically endangered) within the same time series, due to the effects of incorporating habitat quality and the spatial scaling used in RLS parameter estimation. Our results showed that a one-size-fits-all approach to incorporating SRS information in RLS assessment is inappropriate, and we urge caution in conducting range-based assessments with SRS for species for which habitat dependence on specific ecosystem types is incompletely understood. We propose novel revisions to parameter spatial scaling guidelines to improve integration of existing time series data on ecosystem change into the RLS assessment process.


La Lista Roja de Especies Amenazadas (LREA) de la Unión Internacional para la Conservación de la Naturaleza es la herramienta mundial más importante para la evaluación objetiva y repetible del estado de riesgo de extinción de una especie y juega un papel esencial en el seguimiento de la pérdida de la biodiversidad y en la orientación de las acciones de conservación. Los conjuntos de datos obtenidos por telemetría satelital (SRS) sobre la distribución y funcionamiento de los ecosistemas globales tienen un potencial emocionante para informar las evaluaciones de la LREA basadas en la extensión de la distribución de la especie, pero su incorporación dentro de los estudios ha estado restringida por la baja resolución temporal y la poca cobertura de los conjuntos de datos, la falta de inclusión de la pérdida de hábitat causada por la degradación y la nula inclusión de las suposiciones relacionadas con la identificación del cambio de hábitat de distribución para los taxones con una ecología y una dependencia por el hábitat variantes. Analizamos el impacto de las posibles suposiciones con respecto a los tres temas anteriores sobre los resultados de la evaluación de la LREA basada en la distribución de la jutía cubana (Mesocapromys spp.), una especie poco conocida y asociada con manglares. Específicamente, usamos los datos anuales (1985-2018) de Landsat y de la clasificación del uso de suelo y los análisis de degradación del hábitat en diferentes porciones de series temporales internas para simular las evaluaciones de la LREA basadas en la extensión para nuestro taxón de estudio y así explorar la incertidumbre potencial de la evaluación que surge de la cobertura del conjunto de datos SRS temporales. También incorporamos sustitutos de (cambio en) la calidad del hábitat y suposiciones sobre la escala espacial de la extensión del hábitat para la generación de parámetros de la LREA. Encontramos una variación extensa en las evaluaciones simuladas de la LREA específicas de especie y basadas en la extensión. Esta variación estuvo principalmente asociada con la serie temporal sobre la cual se estimaron los parámetros. Sin embargo, los resultados de algunas evaluaciones específicas de especie difirieron hasta en tres categorías (de casi amenazada hasta en peligro crítico) dentro de la misma serie temporal debido a los efectos de la incorporación de la calidad del hábitat y la escala espacial usadas en la estimación de parámetros de la LREA. Nuestros resultados muestran que un enfoque genérico para incorporar la información de SRS en la evaluación de la LREA es inapropiado e instamos precaución al realizar evaluaciones basadas en la extensión con datos SRS para especies cuya dependencia de hábitat por tipos específicos de ecosistemas no está entendida por completo. Proponemos que existan revisiones novedosas de las pautas para los parámetros de las escalas espaciales y así mejorar la integración de los datos existentes de series temporales sobre el cambio en el ecosistema dentro de los procesos de evaluación de RLS. Identificación de las Posibilidades y las Dificultades para la Realización de Evaluaciones de la Lista Roja de la UICN a partir de Información de Hábitat Detectada Remotamente con base en la Información sobre Mamíferos Cubanos Poco Conocidos.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Espécies em Perigo de Extinção , Extinção Biológica , Mamíferos
10.
Conserv Biol ; 35(4): 1288-1298, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33146430

RESUMO

Establishing protected areas (PAs) is an essential strategy to reduce biodiversity loss. However, many PAs do not provide adequate protection due to poor funding, inadequate staffing and equipment, and ineffective management. As part of China's recent economic growth, the Chinese government has significantly increased investment in nature reserves over the past 20 years, providing a unique opportunity to evaluate whether PAs can protect threatened species effectively. We compiled data from published literature on populations of gibbons (Hylobatidae), a threatened taxon with cultural significance, that occurred in Chinese reserves after 1980. We evaluated the ability of these PAs to maintain gibbon habitat and populations by comparing forest cover and human disturbance between reserves and their surrounding areas and modeling the impact of reserve characteristics on gibbon population trends. We also assessed the perspective of reserve staff concerning PA management effectiveness through an online survey. Reserves effectively protected gibbon habitat by reducing forest loss and human disturbance; however, half the reserves lost their gibbon populations since being established. Gibbons were more likely to survive in reserves established more recently, at higher elevation, with less forest loss and lower human impact, and that have been relatively well studied. A larger initial population size in the 1980s was positively associated with gibbon persistence. Although staff of all reserves reported increased investment and improved management over the past 20-30 years, no relationship was found between management effectiveness and gibbon population trends. We suggest early and emphatic intervention is critical to stop population decline and prevent extinction.


Efectos de las Áreas Protegidas sobre la Supervivencia de Gibones Amenazados en China Resumen El establecimiento de áreas protegidas (APs) es una estrategia esencial para la reducción de la pérdida de la biodiversidad. Sin embargo, muchas APs no proporcionan una protección adecuada debido a un mal financiamiento, personal y equipamientos inadecuados y un manejo poco efectivo. Como parte del reciente crecimiento económico en China, el gobierno del país ha incrementado significativamente la inversión en las reservas naturales durante los últimos 20 años, proporcionando así una oportunidad única para evaluar si las APs pueden proteger a las especies amenazadas de manera efectiva. Recopilamos datos de la literatura publicada sobre las poblaciones de gibones (Hylobatidae), un taxón amenazado que cuenta con importancia cultural, que se presentaron en las reservas chinas después de 1980. Evaluamos la habilidad de estas APs para mantener el hábitat y las poblaciones de gibones al comparar la cobertura del bosque y la perturbación humana entre las reservas y las áreas vecinas y al modelar el impacto de las características de la reserva sobre las tendencias poblacionales de los gibones. También evaluamos la perspectiva del personal de la reserva con respecto a la efectividad en el manejo de la AP por medio de una encuesta en línea. Las reservas protegieron efectivamente al hábitat de los gibones mediante la reducción de la pérdida del bosque y de la perturbación humana; sin embargo, la mitad de las reservas perdieron su población de gibones desde su establecimiento. Los gibones tuvieron mayores probabilidades de sobrevivir en las reservas establecidas más recientemente, a una elevación más alta, con menor pérdida de bosque y menor impacto humano, y las cuales han sido relativamente bien estudiadas. Un tamaño de población inicial mayor durante la década de 1980 estuvo asociado positivamente con la permanencia de los gibones. Aunque el personal de todas las reservas reportó un incremento en la inversión y mejoras en el manejo durante los últimos 20-30 años, no encontramos una relación entre la efectividad en el manejo y las tendencias poblacionales de los gibones. Sugerimos que una intervención temprana y empática es crítica para detener la declinación poblacional y prevenir la extinción.


Assuntos
Conservação dos Recursos Naturais , Hylobates , Animais , China , Ecossistema , Espécies em Perigo de Extinção , Humanos
11.
Nature ; 522(7554): 81-4, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-25799987

RESUMO

No large group of recently extinct placental mammals remains as evolutionarily cryptic as the approximately 280 genera grouped as 'South American native ungulates'. To Charles Darwin, who first collected their remains, they included perhaps the 'strangest animal[s] ever discovered'. Today, much like 180 years ago, it is no clearer whether they had one origin or several, arose before or after the Cretaceous/Palaeogene transition 66.2 million years ago, or are more likely to belong with the elephants and sirenians of superorder Afrotheria than with the euungulates (cattle, horses, and allies) of superorder Laurasiatheria. Morphology-based analyses have proved unconvincing because convergences are pervasive among unrelated ungulate-like placentals. Approaches using ancient DNA have also been unsuccessful, probably because of rapid DNA degradation in semitropical and temperate deposits. Here we apply proteomic analysis to screen bone samples of the Late Quaternary South American native ungulate taxa Toxodon (Notoungulata) and Macrauchenia (Litopterna) for phylogenetically informative protein sequences. For each ungulate, we obtain approximately 90% direct sequence coverage of type I collagen α1- and α2-chains, representing approximately 900 of 1,140 amino-acid residues for each subunit. A phylogeny is estimated from an alignment of these fossil sequences with collagen (I) gene transcripts from available mammalian genomes or mass spectrometrically derived sequence data obtained for this study. The resulting consensus tree agrees well with recent higher-level mammalian phylogenies. Toxodon and Macrauchenia form a monophyletic group whose sister taxon is not Afrotheria or any of its constituent clades as recently claimed, but instead crown Perissodactyla (horses, tapirs, and rhinoceroses). These results are consistent with the origin of at least some South American native ungulates from 'condylarths', a paraphyletic assembly of archaic placentals. With ongoing improvements in instrumentation and analytical procedures, proteomics may produce a revolution in systematics such as that achieved by genomics, but with the possibility of reaching much further back in time.


Assuntos
Colágeno Tipo I/química , Fósseis , Mamíferos/classificação , Filogenia , Sequência de Aminoácidos , Animais , Osso e Ossos/química , Bovinos , Colágeno Tipo I/genética , Feminino , Perissodáctilos/classificação , Placenta , Gravidez , Proteômica , América do Sul
12.
Proc Natl Acad Sci U S A ; 115(50): 12769-12774, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30420497

RESUMO

The insular Caribbean until recently contained a diverse mammal fauna including four endemic platyrrhine primate species, all of which died out during the Holocene. Previous morphological studies have attempted to establish how these primates are related to fossil and extant platyrrhines, whether they represent ancient or recent colonists, and whether they constitute a monophyletic group. These efforts have generated multiple conflicting hypotheses, from close sister-taxon relationships with several different extant platyrrhines to derivation from a stem platyrrhine lineage outside the extant Neotropical radiation. This diversity of opinion reflects the fact that Caribbean primates were morphologically extremely unusual, displaying numerous autapomorphies and apparently derived conditions present across different platyrrhine clades. Here we report ancient DNA data for an extinct Caribbean primate: a limited-coverage entire mitochondrial genome and seven regions of nuclear genome for the most morphologically derived taxon, the Jamaican monkey Xenothrix mcgregori We demonstrate that Xenothrix is part of the existing platyrrhine radiation rather than a late-surviving stem platyrrhine, despite its unusual adaptations, and falls within the species-rich but morphologically conservative titi monkey clade (Callicebinae) as sister to the newly recognized genus Cheracebus These results are not congruent with previous morphology-based hypotheses and suggest that even morphologically conservative lineages can exhibit phenetic plasticity in novel environments like those found on islands. Xenothrix and Cheracebus diverged ca. 11 Ma, but primates have been present in the Caribbean since 17.5-18.5 Ma, indicating that Caribbean primate diversity was generated by multiple over-water colonizations.


Assuntos
DNA Antigo/análise , Haplorrinos/genética , Adaptação Fisiológica/genética , Animais , Biodiversidade , Região do Caribe , Núcleo Celular/genética , Fósseis , Genoma Mitocondrial/genética , Filogenia , Água
13.
BMC Evol Biol ; 20(1): 106, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811443

RESUMO

BACKGROUND: The Caribbean offers a unique opportunity to study evolutionary dynamics in insular mammals. However, the recent extinction of most Caribbean non-volant mammals has obstructed evolutionary studies, and poor DNA preservation associated with tropical environments means that very few ancient DNA sequences are available for extinct vertebrates known from the region's Holocene subfossil record. The endemic Caribbean eulipotyphlan family Nesophontidae ("island-shrews") became extinct ~ 500 years ago, and the taxonomic validity of many Nesophontes species and their wider evolutionary dynamics remain unclear. Here we use both morphometric and palaeogenomic methods to clarify the status and evolutionary history of Nesophontes species from Hispaniola, the second-largest Caribbean island. RESULTS: Principal component analysis of 65 Nesophontes mandibles from late Quaternary fossil sites across Hispaniola identified three non-overlapping morphometric clusters, providing statistical support for the existence of three size-differentiated Hispaniolan Nesophontes species. We were also able to extract and sequence ancient DNA from a ~ 750-year-old specimen of Nesophontes zamicrus, the smallest non-volant Caribbean mammal, including a whole-mitochondrial genome and partial nuclear genes. Nesophontes paramicrus (39-47 g) and N. zamicrus (~ 10 g) diverged recently during the Middle Pleistocene (mean estimated divergence = 0.699 Ma), comparable to the youngest species splits in Eulipotyphla and other mammal groups. Pairwise genetic distance values for N. paramicrus and N. zamicrus based on mitochondrial and nuclear genes are low, but fall within the range of comparative pairwise data for extant eulipotyphlan species-pairs. CONCLUSIONS: Our combined morphometric and palaeogenomic analyses provide evidence for multiple co-occurring species and rapid body size evolution in Hispaniolan Nesophontes, in contrast to patterns of genetic and morphometric differentiation seen in Hispaniola's extant non-volant land mammals. Different components of Hispaniola's mammal fauna have therefore exhibited drastically different rates of morphological evolution. Morphological evolution in Nesophontes is also rapid compared to patterns across the Eulipotyphla, and our study provides an important new example of rapid body size change in a small-bodied insular vertebrate lineage. The Caribbean was a hotspot for evolutionary diversification as well as preserving ancient biodiversity, and studying the surviving representatives of its mammal fauna is insufficient to reveal the evolutionary patterns and processes that generated regional diversity.


Assuntos
Tamanho Corporal , Fósseis , Musaranhos/classificação , Animais , DNA Antigo/análise , Filogenia , Índias Ocidentais
14.
Mol Biol Evol ; 34(3): 598-612, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28007976

RESUMO

Retracing complex population processes that precede extreme bottlenecks may be impossible using data from living individuals. The wisent (Bison bonasus), Europe's largest terrestrial mammal, exemplifies such a population history, having gone extinct in the wild but subsequently restored by captive breeding efforts. Using low coverage genomic data from modern and historical individuals, we investigate population processes occurring before and after this extinction. Analysis of aligned genomes supports the division of wisent into two previously recognized subspecies, but almost half of the genomic alignment contradicts this population history as a result of incomplete lineage sorting and admixture. Admixture between subspecies populations occurred prior to extinction and subsequently during the captive breeding program. Admixture with the Bos cattle lineage is also widespread but results from ancient events rather than recent hybridization with domestics. Our study demonstrates the huge potential of historical genomes for both studying evolutionary histories and for guiding conservation strategies.


Assuntos
Bison/genética , Extinção Biológica , Animais , Animais Domésticos/genética , Evolução Biológica , Cruzamento , Bovinos , DNA Antigo/análise , DNA Mitocondrial/genética , Fluxo Gênico/genética , Variação Genética , Genômica/métodos , Hibridização Genética/genética , Filogenia , Análise de Sequência de DNA/métodos
15.
Mol Biol Evol ; 33(12): 3095-3103, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27624716

RESUMO

The mammalian evolutionary tree has lost several major clades through recent human-caused extinctions. This process of historical biodiversity loss has particularly affected tropical island regions such as the Caribbean, an area of great evolutionary diversification but poor molecular preservation. The most enigmatic of the recently extinct endemic Caribbean mammals are the Nesophontidae, a family of morphologically plesiomorphic lipotyphlan insectivores with no consensus on their evolutionary affinities, and which constitute the only major recent mammal clade to lack any molecular information on their phylogenetic placement. Here, we use a palaeogenomic approach to place Nesophontidae within the phylogeny of recent Lipotyphla. We recovered the near-complete mitochondrial genome and sequences for 17 nuclear genes from a ∼750-year-old Hispaniolan Nesophontes specimen, and identify a divergence from their closest living relatives, the Solenodontidae, more than 40 million years ago. Nesophontidae is thus an older distinct lineage than many extant mammalian orders, highlighting not only the role of island systems as "museums" of diversity that preserve ancient lineages, but also the major human-caused loss of evolutionary history.


Assuntos
Evolução Biológica , Eulipotyphla/classificação , Eulipotyphla/genética , Análise de Sequência de DNA/métodos , Animais , Biodiversidade , DNA Antigo/análise , DNA Mitocondrial/genética , Genoma Mitocondrial , Filogenia , Índias Ocidentais
16.
Proc Biol Sci ; 284(1867)2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29167363

RESUMO

Ecosystems have been modified by human activities for millennia, and insights about ecology and extinction risk based only on recent data are likely to be both incomplete and biased. We synthesize multiple long-term archives (over 250 archaeological and palaeontological sites dating from the early Holocene to the Ming Dynasty and over 4400 historical records) to reconstruct the spatio-temporal dynamics of Holocene-modern range change across China, a megadiverse country experiencing extensive current-day biodiversity loss, for 34 mammal species over three successive postglacial time intervals. Our combined zooarchaeological, palaeontological, historical and current-day datasets reveal that both phylogenetic and spatial patterns of extinction selectivity have varied through time in China, probably in response both to cumulative anthropogenic impacts (an 'extinction filter' associated with vulnerable species and accessible landscapes being affected earlier by human activities) and also to quantitative and qualitative changes in regional pressures. China has experienced few postglacial global species-level mammal extinctions, and most species retain over 50% of their maximum estimated Holocene range despite millennia of increasing regional human pressures, suggesting that the potential still exists for successful species conservation and ecosystem restoration. Data from long-term archives also demonstrate that herbivores have experienced more historical extinctions in China, and carnivores have until recently displayed greater resilience. Accurate assessment of patterns of biodiversity loss and the likely predictive power of current-day correlates of faunal vulnerability and resilience is dependent upon novel perspectives provided by long-term archives.


Assuntos
Biodiversidade , Extinção Biológica , Mamíferos , Animais , Arqueologia , China , Bases de Dados Factuais , Paleontologia , Filogenia
17.
Proc Biol Sci ; 284(1861)2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28855367

RESUMO

Historical patterns of diversity, biogeography and faunal turnover remain poorly understood for Wallacea, the biologically and geologically complex island region between the Asian and Australian continental shelves. A distinctive Quaternary vertebrate fauna containing the small-bodied hominin Homo floresiensis, pygmy Stegodon proboscideans, varanids and giant murids has been described from Flores, but Quaternary faunas are poorly known from most other Lesser Sunda Islands. We report the discovery of extensive new fossil vertebrate collections from Pleistocene and Holocene deposits on Sumba, a large Wallacean island situated less than 50 km south of Flores. A fossil assemblage recovered from a Pleistocene deposit at Lewapaku in the interior highlands of Sumba, which may be close to 1 million years old, contains a series of skeletal elements of a very small Stegodon referable to S. sumbaensis, a tooth attributable to Varanus komodoensis, and fragmentary remains of unidentified giant murids. Holocene cave deposits at Mahaniwa dated to approximately 2000-3500 BP yielded extensive material of two new genera of endemic large-bodied murids, as well as fossils of an extinct frugivorous varanid. This new baseline for reconstructing Wallacean faunal histories reveals that Sumba's Quaternary vertebrate fauna, although phylogenetically distinctive, was comparable in diversity and composition to the Quaternary fauna of Flores, suggesting that similar assemblages may have characterized Quaternary terrestrial ecosystems on many or all of the larger Lesser Sunda Islands.


Assuntos
Evolução Biológica , Fósseis , Vertebrados/classificação , Animais , Austrália , Hominidae , Indonésia , Ilhas
18.
Am J Primatol ; 79(3): 1-13, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28118498

RESUMO

Conservation management requires an evidence-based approach, as uninformed decisions can signify the difference between species recovery and loss. The Hainan gibbon, the world's rarest ape, reportedly exploits the largest home range of any gibbon species, with these apparently large spatial requirements potentially limiting population recovery. However, previous home range assessments rarely reported survey methods, effort, or analytical approaches, hindering critical evaluation of estimate reliability. For extremely rare species where data collection is challenging, it also is unclear what impact such limitations have on estimating home range requirements. We re-evaluated Hainan gibbon spatial ecology using 75 hr of observations from 35 contact days over 93 field-days across dry (November 2010-February 2011) and wet (June 2011-September 2011) seasons. We calculated home range area for three social groups (N = 21 individuals) across the sampling period, seasonal estimates for one group (based on 24 days of observation; 12 days per season), and between-group home range overlap using multiple approaches (Minimum Convex Polygon, Kernel Density Estimation, Local Convex Hull, Brownian Bridge Movement Model), and assessed estimate reliability and representativeness using three approaches (Incremental Area Analysis, spatial concordance, and exclusion of expected holes). We estimated a yearly home range of 1-2 km2 , with 1.49 km2 closest to the median of all estimates. Although Hainan gibbon spatial requirements are relatively large for gibbons, our new estimates are smaller than previous estimates used to explain the species' limited recovery, suggesting that habitat availability may be less important in limiting population growth. We argue that other ecological, genetic, and/or anthropogenic factors are more likely to constrain Hainan gibbon recovery, and conservation attention should focus on elucidating and managing these factors. RESEARCH HIGHLIGHTS: Re-evaluation reveals Hainan gibbon home range as c. 1-2 km2 . Hainan gibbon home range is, therefore, similar to other Nomascus gibbons. Limited data for extremely rare species does not necessarily prevent derivation of robust home range estimates.


Assuntos
Espécies em Perigo de Extinção , Comportamento de Retorno ao Território Vital , Hylobates , Animais , Ecossistema , Reprodutibilidade dos Testes , Estações do Ano
19.
Am J Primatol ; 79(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28073165

RESUMO

We describe a species of Hoolock gibbon (Primates: Hylobatidae) that is new to science from eastern Myanmar and southwestern China. The genus of hoolock gibbons comprises two previously described living species, the western (Hoolock hoolock) and eastern hoolock (H. leuconedys) gibbons, geographically isolated by the Chindwin River. We assessed the morphological and genetic characteristics of wild animals and museum specimens, and conducted multi-disciplinary analyses using mitochondrial genomic sequences, external morphology, and craniodental characters to evaluate the taxonomic status of the hoolock population in China. The results suggest that hoolocks distributed to the east of the Irrawaddy-Nmai Hka Rivers, which were previously assigned to H. leuconedys, are morphologically and genetically distinct from those to the west of the river, and should be recognized as a new species, the Gaoligong hoolock gibbon or skywalker hoolock gibbon (H. tianxing sp. nov.). We consider that the new species should be categorized as Endangered under IUCN criteria. The discovery of the new species focuses attention on the need for improved conservation of small apes, many of which are in danger of extinction in southern China and Southeast Asia.


Assuntos
Distribuição Animal , Hylobatidae/classificação , Animais , China , Citocromos b/genética , Hylobatidae/anatomia & histologia , Hylobatidae/genética , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
20.
Am J Primatol ; 79(2): 1-13, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27643665

RESUMO

For Critically Endangered "species of extreme rarity," there is an urgent need to clarify the potential survival of remnant populations. Such populations can be difficult to detect using standard field methods. Local ecological knowledge (LEK) represents an important alternative source of information, but anecdotal reports of rare or possibly extinct species can contain uncertainty and error. The Hainan gibbon (Nomascus hainanus), the world's rarest primate species, is confirmed to only survive as a tiny remnant population in Bawangling National Nature Reserve, China, but unverified gibbon sightings have been reported from other forest areas on Hainan. We conducted a large-scale community interview survey to gather new data on patterns of primate LEK from 709 respondents around seven reserves across Hainan, to investigate the possibility of gibbon survival outside Bawangling and assess whether LEK can provide useful information for conservation management of cryptic remnant populations. Comparative LEK data for gibbons and macaques are consistent with independent data on the relative status of these species across Hainan. Local awareness and experience of gibbons was low across Hainan, including at Bawangling, but we recorded recent anecdotal gibbon reports from most reserves. A follow-up field survey at Limushan Provincial Nature Reserve did not detect gibbons, however, and documented intensive wildlife exploitation within this reserve. All other surveyed landscapes showed some statistically lower levels of respondent awareness, experience, or sighting histories of gibbons compared to Bawangling, and are therefore considered biologically unlikely to support gibbons. Unverified LEK data can provide important insights into the possible status of cryptic remnant populations when assessed carefully and critically in relation to data from known populations.


Assuntos
Espécies em Perigo de Extinção , Hylobates , Animais , China , Ecologia , Dinâmica Populacional
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