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1.
Sci Total Environ ; 912: 169298, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38128653

RESUMO

Border fences have severely impeded the transboundary migration of a number of large mammals worldwide, with central Asia being one of the most impacted. The Marco Polo sheep (Ovis ammon polii), an iconic species of Pamir, is threatened in its transboundary movement by increasing border fencing among their five distributed countries, including Tajikistan, Kyrgyzstan, China, Afghanistan, and Pakistan. In this study, by building ensemble species distribution models, we found that eastern Tajikistan had the largest suitable Macro Polo sheep habitat (about 42 % of the total suitable habitat), followed by China (about 32 %). We used least-cost paths to identify 51 ecological corridors including 5 transboundary ecological corridors, which may be important to maintain connectivity in both domestic and transboundary regions. To assess the potential barrier effect of border fences, we assessed four scenarios (30, 40, 50 and 60°) corresponding to the upper limit of the slope for the construction of fences. In areas too steep for fencing, these could be used by wild sheep to cross barriers or borders and may represent migration or movement routes, defined as natural passages. In the most pessimistic Scenario 60, only 25 migratory passages along the border fences were identified, compared to 997 in the most optimistic scenario (Scenario 30), indicating a strong negative effect of intensive border fencing on the transboundary movement of Marco Polo sheep. The establishment of transnational conservation parks, and ensuring permeability is maintained in key areas, could have a positive impact on the connectivity and persistence of Marco Polo sheep populations, and provide important lessons for other large migratory mammals in transboundary regions.


Assuntos
Ecossistema , Mamíferos , Animais , Ovinos , China , Afeganistão , Quirguistão , Conservação dos Recursos Naturais
2.
Biodivers Data J ; 10: e84365, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761547

RESUMO

Endemic anurans are particularly vulnerable to environmental changes, and are susceptible to population declines because of their restricted distribution ranges. The Murree Hills Frog Nanoranavicina and Hazara Torrent Frog Allopaahazarensis are associated with the torrential streams and nearby clear water pools in subtropical chir pine forest and other forest types, at elevations higher than 1000 m in Pakistan. In this study, we have provided data on the extent of movement of these frog species for the first time. We installed radio transmitters on a total of 13 Murree Hills Frogs and 13 Hazara Torrent Frogs during eight consecutive days in September 2017 and 2018. Our results showed that these frogs did not move long distances along the stream or away from the stream into the forest. All the radio-tracked frogs showed movement of < 3 m. We found a significant differences only in the distance moved by Murree Hills Frogs between the two years studied. Based on our findings, we propose a movement paradigm that focuses on conservation implications for these endemic frogs.

4.
PLoS One ; 16(2): e0240770, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33591975

RESUMO

The order Carnivora, which currently includes 296 species classified into 16 families, is distributed across all continents. The phylogeny and the timing of diversification of members of the order are still a matter of debate. Here, complete mitochondrial genomes were analysed to reconstruct the phylogenetic relationships and to estimate divergence times among species of Carnivora. We assembled 51 new mitogenomes from 13 families, and aligned them with available mitogenomes by selecting only those showing more than 1% of nucleotide divergence and excluding those suspected to be of low-quality or from misidentified taxa. Our final alignment included 220 taxa representing 2,442 mitogenomes. Our analyses led to a robust resolution of suprafamilial and intrafamilial relationships. We identified 21 fossil calibration points to estimate a molecular timescale for carnivorans. According to our divergence time estimates, crown carnivorans appeared during or just after the Early Eocene Climatic Optimum; all major groups of Caniformia (Cynoidea/Arctoidea; Ursidae; Musteloidea/Pinnipedia) diverged from each other during the Eocene, while all major groups of Feliformia (Nandiniidae; Feloidea; Viverroidea) diversified more recently during the Oligocene, with a basal divergence of Nandinia at the Eocene/Oligocene transition; intrafamilial divergences occurred during the Miocene, except for the Procyonidae, as Potos separated from other genera during the Oligocene.


Assuntos
Carnívoros/classificação , Carnívoros/genética , Genoma Mitocondrial/genética , Animais , Evolução Biológica , DNA Mitocondrial/genética , Evolução Molecular , Fósseis , Variação Genética/genética , Filogenia , Análise de Sequência de DNA/métodos
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