scholarly journals Developmental and reproductive physiology of small mammals at high altitude: challenges and evolutionary innovations

2020 ◽  
Vol 223 (24) ◽  
pp. jeb215350
Author(s):  
Cayleih E. Robertson ◽  
Kathryn Wilsterman
Keyword(s):  
High Altitude ◽  
Small Mammals ◽  
Deer Mouse ◽  
Low Oxygen ◽  
Ambient Temperatures ◽  
Mountainous Regions ◽  
The North ◽  
History Of ◽  
Neonatal Physiology ◽  
Reproductive Females

ABSTRACTHigh-altitude environments, characterized by low oxygen levels and low ambient temperatures, have been repeatedly colonized by small altricial mammals. These species inhabit mountainous regions year-round, enduring chronic cold and hypoxia. The adaptations that allow small mammals to thrive at altitude have been well studied in non-reproducing adults; however, our knowledge of adaptations specific to earlier life stages and reproductive females is extremely limited. In lowland natives, chronic hypoxia during gestation affects maternal physiology and placental function, ultimately limiting fetal growth. During post-natal development, hypoxia and cold further limit growth both directly by acting on neonatal physiology and indirectly via impacts on maternal milk production and care. Although lowland natives can survive brief sojourns to even extreme high altitude as adults, reproductive success in these environments is very low, and lowland young rarely survive to sexual maturity in chronic cold and hypoxia. Here, we review the limits to maternal and offspring physiology – both pre-natal and post-natal – that highland-adapted species have overcome, with a focus on recent studies on high-altitude populations of the North American deer mouse (Peromyscus maniculatus). We conclude that a combination of maternal and developmental adaptations were likely to have been critical steps in the evolutionary history of high-altitude native mammals.

Tremadocian (Lower Ordovician) sea-level changes and biotas on the Avalon microcontinent

2011 ◽  
Vol 85 (4) ◽  
pp. 678-694 ◽  
Author(s):  
ED Landing ◽  
Richard A. Fortey
Keyword(s):  
Sea Level ◽  
Sea Level Changes ◽  
Low Oxygen ◽  
Cape Breton Island ◽  
Lower Upper ◽  
The North ◽  
Cape Breton ◽  
Lower Ordovician ◽  
Bottom Waters ◽  
History Of

The Chesley Drive Group, an Upper Cambrian-Lower Ordovician mudstone-dominated unit, is part of the Ediacaran–Ordovician cover sequence on the North American part of the Avalon microcontinent. The upper Chesley Drive Group on McLeod Brook, Cape Breton Island (previously “McLeod Brook Formation”), has two lithofacies-specific Tremadocian biotas. An older low-diversity benthic assemblage (shallow burrowers, Bathysiphon, phosphatic brachiopods, asaphid trilobites) is in lower upper Tremadocian green-gray mudstone. This wave-influenced, slightly dysoxic facies has Bathysiphon–brachiopod shell lags in ripple troughs. The upper fauna (ca. 483 +/- 1 Ma) is in dysoxic-anoxic (d-a), unburrowed, dark gray-black, upper upper (but not uppermost) Tremadocian mudstone with a “mass kill” of the olenid Peltocare rotundifrons (Matthew)—a provincial trilobite in Avalonian North America that likely tolerated low oxygen bottom waters. Scandodus avalonensis Landing n. sp. and Lagenochitina aff. conifundus (Poumot), probable nektic elements and the first upper Tremadocian conodont and chitinozoan reported from Avalon, occur in diagenetic calcareous nodules in the dark gray-black mudstone. An upper Tremadocian transition from lower greenish to upper black mudstone is not exposed on McLeod Brook, but is comparable to a coeval green-black mudstone transition in Avalonian England. The successions suggest that late late Tremadocian (probable Baltic Hunnebergian Age) sea level was higher in Avalon than is suggested from successions on other paleocontinents. The Tremadocian sea-level history of Avalon was a shoaling-deepening-shoaling sequence from d-a black mudstone (lower Tremadocian), to dysoxic green mudstone (lower upper Tremadocian), and back to black mudstone (upper upper Tremadocian).Scandodus Lindström is emended, with the early species S. avalonensis Landing n. sp. assigned to the emended Family Protopanderodontidae. Triangulodus Van Wamel is considered a junior synonym of Scandodus. Peltocare rotundifrons is emended on the basis of complete specimens.

The significance of historical factors for the cholology of Collembola diversity

2018 ◽  
pp. 87-98
Author(s):  
Kaprus I.
Keyword(s):  
Evolutionary History ◽  
Adaptive Potential ◽  
Postglacial Colonization ◽  
Mountainous Regions ◽  
The North ◽  
Last Glaciation ◽  
Historical Factors ◽  
History Of ◽  
Centers Of Endemism

It is established that historical factors are important in the formation of modern areas of Collembola. However, the role of ecological and historical factors in the chorology of separate groups of Collembola is different in connection with the evolutionary history of the taxa and their adaptive potential. The significance of regional faunogenetic processes in the formation of the modern areas of the Collembola of Eurasia is increasing in the north-south direction. The main centers of endemism of Collembola of the temperate zone are concentrated in mountainous regions, as well as in the hills adjoining them, which could serve as the main collembolan refugia during the last glaciation. The faunae of plains are mainly of migratory origin. The hypothesis on the predominance of autochthonous processes in the formation of regional collembolan faunae on the territory of Ukraine and their multiregional postglacial colonization is formulated.

scholarly journals EPAS1 variants in high altitude Tibetan wolves were selectively introgressed into highland dogs

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3522 ◽  
Author(s):  
Bridgett vonHoldt ◽  
Zhenxin Fan ◽  
Diego Ortega-Del Vecchyo ◽  
Robert K. Wayne
Keyword(s):  
High Altitude ◽  
Coat Color ◽  
Small Region ◽  
High Elevation ◽  
Domestic Dogs ◽  
Gray Wolf ◽  
Low Oxygen ◽  
Chromosome 10 ◽  
Gray Wolves ◽  
History Of

Background Admixture can facilitate adaptation. For example, black wolves have obtained the variant causing black coat color through past hybridization with domestic dogs and have higher fitness than gray colored wolves. Another recent example of the transfer of adaptive variation between the two species has been suggested by the similarity between high altitude Tibetan mastiffs and wolves at the EPAS1 gene, a transcription factor induced in low oxygen environments. Methods Here, we investigate the directionality of admixture in EPAS1 between 28 reference highland gray wolves, 15 reference domestic dogs, and 21 putatively admixed highland wolves. This experimental design represents an expanded sample of Asian dogs and wolves from previous studies. Admixture was inferred using 17,709 publicly available SNP genotypes on canine chromosome 10. We additionally conducted a scan for positive selection in the highland dog genome. Results We find an excess of highland gray wolf ancestry at the EPAS1 locus in highland domestic dogs, suggesting adaptive introgression from wolves to dogs. The signal of admixture is limited in genomic extent to a small region on chromosome 10, indicating that it is the focus of selection in an oxygen-limited environment. Discussion Our results suggest that an adaptive variant of EPAS1 in highland wolves was transferred to highland dogs, carrying linked variants that potentially function in hypoxia response at high elevation. The intertwined history of dogs and wolves ensures a unique evolutionary dynamic where variants that have appeared in the history of either species can be tested for their effects on fitness under natural and artificial selection. Such coupled evolutionary histories may be key to the persistence of wild canines and their domesticated kin given the increasing anthropogenic modifications that characterize the future of both species.

The Policy of the White Movement in the North Caucasus in 1919—1920 in the Assessments of the Leaders of the Mountain National Movement (Based on the Materials of the Mountain Émigré Press)

Istoriya ◽  
2021 ◽  
Vol 12 (10 (108)) ◽  
pp. 0
Author(s):  
Timur Matiev
Keyword(s):  
North Caucasus ◽  
Policy And Practice ◽  
The Caucasus ◽  
Mountainous Regions ◽  
The Past ◽  
The North ◽  
National Question ◽  
History Of ◽  
Relationship Of ◽  
The Relationship

The article is devoted to the analysis of the peculiarities of the folding and evolution of the attitude of mountain democratic leaders to the policy and practice of the White Guard political and military leadership, as well as to the actions of the troops of the Volunteer Army in the mountainous regions of the North Caucasus. Particular attention is paid to such moments as the position of the white movement on the rights of nations to self-determination; the relationship of whites with the Union of the United Highlanders of the North Caucasus and Dagestan, and after that — with the Mountain Republic; their position in relation to the land and national question in the North Caucasus. The evolution of views and assessments of highland emigration is traced both on the role and place of the White movement in the recent history of the region, and on the past and future of historical ties between the North Caucasus and Russia. An attempt is made to analyze the changes in a number of accents in these assessments over time and under the influence of the development of the situation in the Caucasus, the USSR and the world as a whole.

Ras al Khaimah: further archaeological discoveries

Antiquity ◽  
1976 ◽  
Vol 50 (200) ◽  
pp. 216-222
Author(s):  
Beatrice De Cardi
Keyword(s):  
United Arab Emirates ◽  
The State ◽  
Focused Attention ◽  
North East ◽  
The North ◽  
History Of ◽  
The City

Ras a1 Khaimah is the most northerly of the seven states comprising the United Arab Emirates and its Ruler, H. H. Sheikh Saqr bin Mohammad al-Qasimi, is keenly interested in the history of the state and its people. Survey carried out there jointly with Dr D. B. Doe in 1968 had focused attention on the site of JuIfar which lies just north of the present town of Ras a1 Khaimah (de Cardi, 1971, 230-2). Julfar was in existence in Abbasid times and its importance as an entrep6t during the sixteenth and seventeenth centuries-the Portuguese Period-is reflected by the quantity and variety of imported wares to be found among the ruins of the city. Most of the sites discovered during the survey dated from that period but a group of cairns near Ghalilah and some long gabled graves in the Shimal area to the north-east of the date-groves behind Ras a1 Khaimah (map, FIG. I) clearly represented a more distant past.

Sequencing Analysis and Phylogenetic Tree of HPV Isolated from Breast Cancer Patients at Thi-Qar Province/Iraq

2020 ◽  
pp. 37-40
Keyword(s):  
Nucleotide Sequence ◽  
Phylogenetic Tree ◽  
Evolutionary Relationship ◽  
Nucleotide Sequencing ◽  
Sequencing Analysis ◽  
Breast Cancer Patients ◽  
The North ◽  
Formalin Fixed Paraffin ◽  
Formalin Fixed Paraffin Embedded ◽  
History Of

Genetic variety examination has demonstrated fundamental to the understanding of the epidemiological and developmental history of Papillomavirus (HPV), for the development of accurate diagnostic tests and for efficient vaccine design. The HPV nucleotide diversity has been investigated widely among high-risk HPV types. To make the nucleotide sequence of HPV and do the virus database in Thi-Qar province, and compare sequences of our isolates with previously described isolates from around the world and then draw its phylogenetic tree, this study done. A total of 6 breast formalin-fixed paraffin-embedded (FFPE) of the female patients were included in the study, divided as 4 FFPE malignant tumor and 2 FFPE of benign tumor. The PCR technique was implemented to detect the presence of HPV in breast tissue, and the real-time PCR used to determinant HPV genotypes, then determined a complete nucleotide sequence of HPV of L1 capsid gene, and draw its phylogenetic tree. The nucleotide sequencing finding detects a number of substitution mutation (SNPs) in (L1) gene, which have not been designated before, were identified once in this study population, and revealed that the HPV16 strains have the evolutionary relationship with the South African race, while, the HPV33 and HPV6 showing the evolutionary association with the North American and East Asian race, respectively.

TBE in Italy

2019 ◽  
Author(s):  
Valentina Tagliapietra ◽  
Flavia Riccardo ◽  
Giovanni Rezza
Keyword(s):  
Case Series ◽  
East Part ◽  
Mountainous Regions ◽  
North East ◽  
The North ◽  
Tick Borne Encephalitis ◽  
Low Incidence

Italy is considered a low incidence country for tick-borne encephalitis (TBE) in Europe. Areas at higher risk for TBE in Italy are geographically clustered in the forested and mountainous regions and provinces in the north east part of the country, as suggested by TBE case series published over the last decade.

TBE in Italy

2020 ◽  
Keyword(s):  
Surveillance System ◽  
Ad Hoc ◽  
National Level ◽  
Case Series ◽  
Incidence Rates ◽  
Mountainous Regions ◽  
North East ◽  
The North ◽  
Tick Borne Encephalitis ◽  
Low Incidence

Italy is considered a low-incidence country for tick-borne encephalitis (TBE) in Europe.1 Areas at higher risk for TBE in Italy are geographically clustered in the forested and mountainous regions and provinces in the north east part of the country, as suggested by TBE case series published over the last decade.2-5 A national enhanced surveillance system for TBE has been established since 2017.6 Before this, information on the occurrence of TBE cases at the national level in Italy was lacking. Both incidence rates and the geographical distribution of the disease were mostly inferred from endemic areas where surveillance was already in place, ad hoc studies and international literature.1

North American Association for the Study of Religion (NAASR)

2015 ◽  
Vol 44 (2) ◽  
pp. 29-30
Author(s):  
Matt Sheedy
Keyword(s):  
North American ◽  
American Association ◽  
The North ◽  
History Of

I interviewed Russell McCutcheon back in March 2015, about his new role as president of the North American Association for the Study of Religion (NAASR), asking him about the history of the organization, goals for his tenure, and developments for NAASR’s upcoming conference in Atlanta in November 2015.

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