Morphological relationships among subspecies of the Rufous-collared Sparrow, Zonotrichia capensis

1985 ◽  
Vol 63 (10) ◽  
pp. 2383-2388 ◽  
Author(s):  
Paul Handford
Keyword(s):  
Intraspecific Variation ◽  
Environmental Effects ◽  
Local Environment ◽  
Andes Mountains ◽  
Museum Specimens ◽  
High Latitudes ◽  
High Altitudes ◽  
Southern Andes ◽  
Zonotrichia Capensis ◽  
Phenetic Relationships

The phenetic relationships among 22 described subspecies of Zonotrichia capensis, the Rufous-collared Sparrow, are investigated by analyses of variation in six external metric variables taken from over 1500 museum specimens. Both sexes show the same marked dichotomy between two groups of subspecies: pulacayensis, sanborni, antofagastae, chilensis, choraules, and australis versus all others. These six subspecies are from temperate high altitudes and high latitudes and occupy a geographically contiguous region in the southern Andes mountains and Patagonia. Within these two subgroups there is extensive overlap among individuals; finer division of the subspecies is difficult, and involves the association of subspecies from geographically disjunct regions. Thus the taxonomic hierarchy appears to be a poor representation of variation of the characters considered here. The association of geographically disjunct forms suggests that intraspecific variation in these characters reflects the local environment (via selection and (or) environmental effects) rather than historical (genealogical) relationships.

scholarly journals The influence of topography on vertical velocity of air in relation to severe storms near the Southern Andes Mountains

2015 ◽  
Vol 156 ◽  
pp. 91-101 ◽  
Author(s):  
A. de la Torre ◽  
H. Pessano ◽  
R. Hierro ◽  
J.R. Santos ◽  
P. Llamedo ◽  
...  
Keyword(s):  
Vertical Velocity ◽  
Andes Mountains ◽  
Southern Andes ◽  
Severe Storms

Classification of tsetse flies Glossina spp. (Diptera: Glossinidae) by gas chromatographic analysis of cuticular components

1993 ◽  
Vol 83 (4) ◽  
pp. 507-515 ◽  
Author(s):  
D.A. Carlson ◽  
S.K. Milstrey ◽  
S.K. Narang
Keyword(s):  
Liquid Chromatography ◽  
Solvent Extraction ◽  
Chromatographic Analysis ◽  
Group Classification ◽  
Tsetse Flies ◽  
Gas Liquid Chromatography ◽  
Museum Specimens ◽  
Glossina Tachinoides ◽  
Phenetic Relationships

AbstractGas liquid chromatography (GC) was used to analyse the cuticular alkanes of 26 species and subspecies of tsetse flies (Glossina spp.). Unique interspecific and intraspecific (males vs. females) chromatographic patterns were observed. Solvent extraction of dried museum specimens and fresh specimens were equally successful, and left specimens undamaged. GC peaks were used as characters with one of five character states per peak, to show phenetic relationships among species by sex using a UPGMA algorithm, using 23 peaks for males and 40 peaks for females. Comparisons among species of the morsitans group often agreed with recognized morsitans group classification using morphological techniques, with G. austeni Newstead being somewhat aberrant. Glossina tachinoides Westwood was less closely related to others in the palpalis group than previously described using morphology. Eleven members of the rarely studied fusca group were also classified by this methodology.

scholarly journals Proposal of 'Candidatus Frankia alpina', the uncultured symbiont of Alnus alnobetula and A. incana that forms spore-containing nitrogen-fixing root nodules

2020 ◽  
Vol 70 (10) ◽  
pp. 5453-5459 ◽  
Author(s):  
Adrien C. Meynier Pozzi ◽  
Aude Herrera-Belaroussi ◽  
Guillaume Schwob ◽  
Hector H. Bautista-Guerrero ◽  
Lorine Bethencourt ◽  
...  
Keyword(s):  
Root Nodules ◽  
Molecular Clusters ◽  
High Latitudes ◽  
Nitrogen Fixing ◽  
High Altitudes ◽  
Content Type ◽  
Link Type ◽  
Dicotyledonous Plants ◽  
Alpine Environments ◽  
Species Being

The members of the genus Frankia are, with a few exceptions, a group of nitrogen-fixing symbiotic actinobacteria that nodulate mostly woody dicotyledonous plants belonging to three orders, eight families and 23 genera of pioneer dicots. These bacteria have been characterized phylogenetically and grouped into four molecular clusters. One of the clusters, cluster 1 contains strains that induce nodules on Alnus spp. (Betulaceae), Myrica spp., Morella spp. and Comptonia spp. (Myricaceae) that have global distributions. Some of these strains produce not only hyphae and vesicles, as other cluster 1 strains do, but also numerous sporangia in their host symbiotic tissues, hence their phenotype being described as spore-positive (Sp+). While Sp+ strains have resisted repeated attempts at cultivation, their genomes have recently been characterized and found to be different from those of all described species, being markedly smaller than their phylogenetic neighbours. We thus hereby propose to create a 'Candidatus Frankia alpina' species for some strains present in nodules of Alnus alnobetula and A. incana that grow in alpine environments at high altitudes or in subarctic environments at high latitudes.

scholarly journals Nitrogen isotopic composition of plants and soil in an arid mountainous terrain: sunny slope versus shady slope

2017 ◽  
Author(s):  
Chongjuan Chen ◽  
Yufu Jia ◽  
Yuzhen Chen ◽  
Imran Mehmood ◽  
Yunting Fang ◽  
...  
Keyword(s):  
Environmental Effects ◽  
Regional Scale ◽  
Local Environment ◽  
Global Scale ◽  
Influential Factors ◽  
N Cycling ◽  
N Availability ◽  
Soil N ◽  
The Difference ◽  
Soil Δ15n

Abstract. Nitrogen cycling is tightly associated with environment. Sunny slope of a given mountain could significantly differ from shady slope in environment. Thus, N cycling should also be different between the two slopes. Since leaf δ15N, soil δ15N and △δ15Nleaf-soil (△δ15Nleaf-soil = leaf δ15N − soil δ15N) could reflect the N cycling characteristics, we put forward a hypothesis that leaf δ15N, soil δ15N and △δ15Nleaf-soil should differ across the two slopes. However, such a comparative study between two slopes has never been conducted yet. In addition, environmental effects on leaf and soil δ15N derived from studies at global scale were often found to be different from that at regional scale. This led to our argument that environmental effects on leaf and soil δ15N could depend on local environment. To confirm our hypothesis and argument, we measured leaf and soil δ15N on the sunny and shady slopes of Mount Tianshan. Remarkable environment differences between the two slopes provided an ideal opportunity for our test. The study showed that leaf δ15N, soil δ15N and △δ15Nleaf-soil on the sunny slope were greater than that on the shady slope although the difference in soil δ15N was not significant. The result confirmed our hypothesis and suggested that the sunny slope has higher soil N transformation rates and soil N availability than the shady slope. Besides, this study observed that the significant influential factors of leaf δ15N were temperature, precipitation, leaf N, leaf C / N and silt / clay ratio on the shady slope, whereas on the sunny slope only leaf C / N was related to leaf δ15N. The significant influential factors of soil δ15N were temperature, precipitation and silt / clay ratio on the shady slope, whereas on the sunny slope MAP and soil moisture exerted significant effects. Precipitation exerted contrary effects on soil δ15N between the two slopes. Thus, this study supported our argument that the relationships between leaf and soil δ15N and environmental factors are local-dependent.

scholarly journals Fast descent routes from within or near the stratosphere to the surface at Fukuoka, Japan, studied using <sup>7</sup>Be measurements and trajectory calculations

2016 ◽  
Vol 16 (10) ◽  
pp. 6241-6261 ◽  
Author(s):  
Hisanori Itoh ◽  
Yukinori Narazaki
Keyword(s):  
Potential Temperature ◽  
Rear Side ◽  
High Latitudes ◽  
High Altitudes ◽  
Sharp Drop ◽  
Near Surface ◽  
Isentropic Surface ◽  
High Concentrations ◽  
Surface Disturbances ◽  
Fast Descent

Abstract. By using high concentrations of 7Be as an indicator, we clarify fast descent routes from within or near the stratosphere to Earth's surface, with the study site being in Fukuoka, Japan. Most routes arise from high latitudes through the following processes. First, the descent associated with a tropopause fold occurs, followed by southward movement with slow descent at the rear side of a strong trough. Because this motion occurs along an isentropic surface, the descending air parcels nearly conserve the potential temperature. As an extension, a strong descent associated with a sharp drop in the isentropic-surface height occurs at the southern edge of the trough; this transports air parcels to low altitudes. This process involves irreversible phenomena such as filamentation and cutoff of potential vorticity. Finally, upon meeting appropriate near-surface disturbances, parcels at low altitudes are transported to Earth's surface.In some cases, parcels descend within midlatitudes. In such routes, because the potential temperature is much higher at high altitudes than at low altitudes, descent with conservation of the potential temperature is impossible, and the potential temperature decreases along the trajectories through mixing.The prevalence of the high-latitude route is explained as follows. In the midlatitude route, because parcels at high and relatively low altitudes mix, the high concentrations of 7Be included in high-altitude parcels are difficult to maintain. Therefore, for parcels to arrive at low altitudes in the midlatitude while maintaining high concentrations of 7Be, i.e., conserving the potential temperature, their area of origin should be high altitudes in high latitudes where the potential temperature is almost the same as that in the arrival area.In spring, tropopause folds are frequent in high latitudes, disturbances in the southward transport of parcels are strong, and disturbances occur by which parcels descend to the surface. Therefore, high concentrations of 7Be occur most frequently in spring.

scholarly journals Geographical distributions of mesospheric gravity wave activity before and after major sudden stratospheric warmings observed by Aura/MLS

2019 ◽  
Author(s):  
Klemens Hocke ◽  
Jonas Hagen ◽  
Franziska Schranz ◽  
Leonie Bernet
Keyword(s):  
Gravity Wave ◽  
Polar Vortex ◽  
Small Region ◽  
Horizontal Resolution ◽  
Wave Activity ◽  
High Latitudes ◽  
Wave Maps ◽  
Southern Andes ◽  
Stratospheric Polar Vortex ◽  
Before And After

Abstract. Observations of the global distribution of mesospheric gravity wave activity are rare. To our knowledge there exist only a few articles showing global maps of gravity wave potential energy in the mesosphere derived from observations of the instrument SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) on NASA's satellite TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics). In the present study, we find that the geopotential height (GPH) measurements of the instrument MLS (Microwave Limb Sounder) on NASA's satellite Aura are sensitive to mesospheric gravity waves with horizontal wavelengths between 200 and 1500 km. We apply a data analysis which evaluates the standard deviation of horizontal GPH perturbations at a fixed pressure level and along the orbit of the sounding volume of Aura/MLS. The orographic waves from the Southern Andes in August serve as a test signal for the horizontal resolution and sensitivity of the method. We find enhanced gravity wave activity in the lower, middle, and upper mesosphere in a small region over the Southern Andes. It seems that the horizontal resolution of the mesospheric gravity wave maps provided by Aura/MLS is higher than those of TIMED/SABER. We apply the method to estimate the global distributions of mesospheric gravity wave activity before and after the major sudden stratospheric warmings (SSWs) of January 21, 2006, January 24, 2009, and January 6, 2013 using 30 day intervals of Aura/MLS observations of GPH. It seems that the gravity wave activity in the lower mesosphere over the subtropical convection regions of the summer hemisphere are decreased after the SSW of January 21, 2006. The gravity wave activity in the lower and middle mesosphere over middle and high latitudes (40° N to 70° N) of the winter hemisphere is decreased after the SSW of January 24, 2009. The major SSW of January 6, 2013 is preceded by enhanced mesospheric gravity wave activity over Eurasia at high latitudes (40° N to 60° N). This asymmetric gravity wave activity in the lower mesosphere is coincident with a long-lasting stay of the stratospheric polar vortex mainly in the Eurasian longitude sector before the SSW of January 6, 2013. In case of the SSW 2009 and SSW 2013, the gravity wave activity is enhanced at latitudes poleward of 70° N in the lower and middle mesosphere after the SSWs.

scholarly journals UPDATING THE TAXONOMY AND DISTRIBUTION OF LIPAROSCELIS PALLIDISPINA STÅL, 1873 (ORTHOPTERA: TETTIGONIIDAE: PSEUDOPHYLLINAE)

2018 ◽  
Vol 17 ◽  
pp. 80-99
Author(s):  
Sheyla Yong
Keyword(s):  
Geographical Distribution ◽  
Museum Specimens ◽  
Monotypic Genus ◽  
High Altitudes ◽  
Species Diagnosis

A detailed complement to the description of the Mexican endemic Pseudophyllinae Liparoscelis pallidispina Stål, 1873 is herein presented, based on several old museum specimens plus recently collected adults. As results, the species diagnosis is updated according to the current taxonomical standards for the order. Moreover, its geographical distribution is clarified and the first precise records of this monotypic genus are given for Michoacán, México and Guerrero States, all of them located at moderately high altitudes on the southern slopes of the Transverse Neovolcanic Belt, above the northeastern reaches of the Balsas Basin. A thorough illustrative complement, which includes a precise map and color photographs of habitus, main morphologically diagnostic structures, habitat and microhabitat.

scholarly journals O<sup>+</sup> and H<sup>+</sup> ion heat fluxes at high altitudes and high latitudes

2014 ◽  
Vol 32 (8) ◽  
pp. 1043-1057 ◽  
Author(s):  
I. A. Barghouthi ◽  
H. Nilsson ◽  
S. H. Ghithan
Keyword(s):  
Heat Flux ◽  
Particle Interaction ◽  
Velocity Distribution Function ◽  
Heat Fluxes ◽  
High Latitudes ◽  
High Altitudes ◽  
Ion Heating ◽  
Maxwellian Plasma ◽  
Field Lines ◽  
Ion Velocity Distribution Function

Abstract. Higher order moments, e.g., perpendicular and parallel heat fluxes, are related to non-Maxwellian plasma distributions. Such distributions are common when the plasma environment is not collision dominated. In the polar wind and auroral regions, the ion outflow is collisionless at altitudes above about 1.2 RE geocentric. In these regions wave–particle interaction is the primary acceleration mechanism of outflowing ionospheric origin ions. We present the altitude profiles of actual and "thermalized" heat fluxes for major ion species in the collisionless region by using the Barghouthi model. By comparing the actual and "thermalized" heat fluxes, we can see whether the heat flux corresponds to a small perturbation of an approximately bi-Maxwellian distribution (actual heat flux is small compared to "thermalized" heat flux), or whether it represents a significant deviation (actual heat flux equal or larger than "thermalized" heat flux). The model takes into account ion heating due to wave–particle interactions as well as the effects of gravity, ambipolar electric field, and divergence of geomagnetic field lines. In the discussion of the ion heat fluxes, we find that (1) the role of the ions located in the energetic tail of the ion velocity distribution function is very significant and has to be taken into consideration when modeling the ion heat flux at high altitudes and high latitudes; (2) at times the parallel and perpendicular heat fluxes have different signs at the same altitude. This indicates that the parallel and perpendicular parts of the ion energy are being transported in opposite directions. This behavior is the result of many competing processes; (3) we identify altitude regions where the actual heat flux is small as compared to the "thermalized" heat flux. In such regions we expect transport equation solutions based on perturbations of bi-Maxwellian distributions to be applicable. This is true for large altitude intervals for protons, but only the lowest altitudes for oxygen.

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