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1.
Nature ; 605(7909): 285-290, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35477765

RESUMEN

Comprehensive assessments of species' extinction risks have documented the extinction crisis1 and underpinned strategies for reducing those risks2. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction3. Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods4-7. Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs6. Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened-confirming a previous extrapolation8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods-agriculture, logging, urban development and invasive species-although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles-including most species of crocodiles and turtles-require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Reptiles , Caimanes y Cocodrilos , Anfibios , Animales , Biodiversidad , Aves , Mamíferos , Filogenia , Reptiles/clasificación , Medición de Riesgo , Tortugas
2.
Curr Biol ; 30(12): R721-R735, 2020 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-32574638

RESUMEN

Turtles and tortoises (chelonians) have been integral components of global ecosystems for about 220 million years and have played important roles in human culture for at least 400,000 years. The chelonian shell is a remarkable evolutionary adaptation, facilitating success in terrestrial, freshwater and marine ecosystems. Today, more than half of the 360 living species and 482 total taxa (species and subspecies combined) are threatened with extinction. This places chelonians among the groups with the highest extinction risk of any sizeable vertebrate group. Turtle populations are declining rapidly due to habitat loss, consumption by humans for food and traditional medicines and collection for the international pet trade. Many taxa could become extinct in this century. Here, we examine survival threats to turtles and tortoises and discuss the interventions that will be needed to prevent widespread extinction in this group in coming decades.


Asunto(s)
Conservación de los Recursos Naturales , Tortugas , Animales , Especies en Peligro de Extinción , Extinción Biológica , Dinámica Poblacional
3.
Intern Med J ; 50(12): 1505-1513, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31841252

RESUMEN

BACKGROUND: Chronic respiratory disorders are highly prevalent in Aboriginal Australian population, including chronic obstructive pulmonary disease (COPD) and bronchiectasis. However, there is paucity of information in the literature among Aboriginal patients with underlying COPD with and without bronchiectasis. AIMS: In this retrospective study we evaluated the demographic and clinical characteristics of adult Aboriginal Australian patients with a clinical diagnosis of COPD with and without bronchiectasis from the remote communities of the Northern Territory of Australia. METHODS: Clinical records were reviewed to extract information on demographics, respiratory and medical comorbid conditions, COPD directed treatment, hospital admission frequency and exacerbations. Chest radiology were reviewed to evaluate the presence or absence of bronchiectasis. Spirometry results, sputum culture and cardiac investigations were also recorded. RESULTS: Of the 767 patients assessed in the remote community respiratory outreach clinics 380 (49%) patients had a clinical diagnosis of COPD. Chest X-ray and computed tomography scan were available to evaluate the presence of bronchiectasis in 258 patients. Of the 258/380 patients, 176/258 (68.2%) were diagnosed to have COPD alone and 82/258 (31.8%) had bronchiectasis along with COPD. The mean age was 56 and 59 years among patients with and without bronchiectasis, respectively, and 57% were males with bronchiectasis. Patients with bronchiectasis had lower body mass index (22 vs 24 kg/m2 ), frequent hospital admissions (2.0 vs 1.5/year) and productive cough (32.1% vs 28.9%). Spirometry showed 77% had forced expiratory volume in 1 s (FEV1 )/forced vital capacity ratio <0.7. In 81% and 75% of patients with and without bronchiectasis the FEV1 /forced vital capacity ratio was <0.7 and the mean FEV1 was 39% and 43% respectively. CONCLUSIONS: About 32% of Aboriginal Australians had co-existent bronchiectasis with COPD. Lower body mass index, productive cough, frequent hospital admission and marginally more severe reduction in lung function were noted among patients with COPD and bronchiectasis compared to those with COPD in isolation.


Asunto(s)
Bronquiectasia , Enfermedad Pulmonar Obstructiva Crónica , Adulto , Bronquiectasia/diagnóstico , Bronquiectasia/epidemiología , Femenino , Volumen Espiratorio Forzado , Humanos , Pulmón , Masculino , Persona de Mediana Edad , Nativos de Hawái y Otras Islas del Pacífico , Northern Territory/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Estudios Retrospectivos , Espirometría , Capacidad Vital
4.
Int J Chron Obstruct Pulmon Dis ; 14: 2205-2217, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31576117

RESUMEN

Background: The Aboriginal population of Australia has a higher burden of chronic health conditions than non-Aboriginal Australians. However, there is a paucity of data on clinical and demographic characteristics of chronic obstructive pulmonary disease (COPD) in this population. Method: In this retrospective study we evaluated the clinical, demographic and environmental influences in adult Aboriginal patients with COPD living in the regional and remote communities of the Northern Territory of Australia. Results: There were 380 patients (49%) with a diagnosis of COPD of the 767 patients referred to specialist respiratory outreach clinics. The mean age was 57 years (56% were female) and mean±SD BMI was 24.30±7.01 kg/m2. Smoking history was noted in 93% of the study cohort. The most common respiratory symptom was shortness of breath in 62%, and inhaled medications (salbutamol, tiotropium, salmeterol/fluticasone) were used by 79%, 44% and 58% of patients, respectively. Spirometry showed obstructive impairment (FEV1/FVC <0.7) in 79% (0.56±0.17), with mean FEV1 42% of predicted, and a bronchodilator response was present in 28.6%. Comorbid bronchiectasis was diagnosed in 49.8% along with COPD. The relationship between COPD and community demography showed a higher proportion of smokers and those with underlying bronchiectasis to have lower FEV1/FVC ratios. Communities with a higher proportion of asthma were younger and had higher smoking rates. Mortality increased with increasing number of exacerbations and hospital admissions. Conclusion: The Aboriginal population with COPD has a higher prevalence of smoking, moderate to severe airflow obstruction on spirometry and frequently co-diagnosed bronchiectasis with increased severity of ventilatory impairment.


Asunto(s)
Nativos de Hawái y Otras Islas del Pacífico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Northern Territory/epidemiología , Estudios Retrospectivos
5.
Zoology (Jena) ; 120: 92-100, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27552858

RESUMEN

Amazon rivers can be divided into three groups (black, white and clear waters) according to the origin of their sediment, dissolved nutrient content, and vegetation. White water rivers have high sediment loads and primary productivity, with abundant aquatic and terrestrial plant life. In contrast, black water rivers are acid and nutrient-poor, with infertile floodplains that support plant species exceptionally rich in secondary chemical defences against herbivory. In this study, we reviewed available information on the diet of Amazon sideneck river turtles (Family Podocnemididae). Our aim was to test the relationship between water type and diet of podocnemidids. We also took into account the effects of season, size, age, sex and phylogeny. Based on our review, turtles of this family are primarily herbivorous but opportunistic, consuming from 46 to 99% (percent volume) of vegetable matter depending on species, sex, season and location. There was no significant correlation between the maximum carapace size of a species and vegetable matter consumed. When the available information on diet, size and habitat was arranged on the podocnemidid phylogeny, no obvious evolutionary trend was evident. The physicochemical properties of the inhabited water type indirectly influence the average volume of total vegetable matter consumed. Species with no specialised stomach adaptations for herbivory consumed smaller amounts of hard to digest vegetable matter (i.e. leaves, shoots and stems). We propose that turtles with specialized digestive tracts may have an advantage in black water rivers where plant chemical defences are more common. Despite limitations of the published data our review highlights the overall pattern of diet in the Podocnemididae and flags areas where more studies are needed.


Asunto(s)
Tamaño Corporal , Conducta Alimentaria/fisiología , Filogenia , Estaciones del Año , Tortugas/genética , Tortugas/fisiología , Animales , Ríos
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