THE GENUS CLASTOPTERA (CERCOPIDAE)

1927 ◽  
Vol 59 (5) ◽  
pp. 103-112 ◽  
Author(s):  
E. D. Ball
Keyword(s):  
Life History ◽  
South America ◽  
Food Plant ◽  
The Other ◽  
Number Of Species ◽  
North And South America ◽  
North And South

The members of this genus are all small and globose and are easily separated from other Cercopidae, but here the easy part abruptly ends. The varieties are widely variable in size, form and color, ranging in most species from large pale forms through spotted, striped and variously ornamented ones on down through coppery and bronzy shades to small black forms at the other extreme. The representatives of this group are distributed through North and South America where some 68 or 70 different forms have been named. All of the earlier ones and most of those of later date have been founded on size and color markings alone, which vary with the sex, the food plant, the environment and in some cases at least with the season. Under the circumstances it is manifestly impossible to determine the number of species involved or to work out a stable nomenclature until extended collection and careful life history has been done in the areas involved.

CYTOTAXONOMIC STUDIES ON NEW WORLD ANEMONE (SECTION ERIOCEPHALUS) WITH WOODY ROOTSTOCKS

1964 ◽  
Vol 42 (7) ◽  
pp. 891-922 ◽  
Author(s):  
G. Boraiah ◽  
Margaret Heimburger
Keyword(s):  
South America ◽  
Rocky Mountains ◽  
New World ◽  
The Other ◽  
Marker Chromosomes ◽  
Close Relationship ◽  
Morphological Differences ◽  
North And South America ◽  
North And South

New World taxa of Anemone L. (section Eriocephalus Hook. f. & Thoms.) with woody rootstocks have few morphological differences on which to delimit species. With the aid of data from cytological, distributional, and hybridization studies, the following species with ternate leaves could be recognized: A. multiceps (Greene) Standl., A. multifida Poir., 2n 32, A. tetonensis Porter, 2n 32, A. stylosa Nelson, 2n 32. A. drummondii S. wats., 2n 32, and A. lithophila Rydb., 2n 48, are complexes with two or more taxa in each. All these taxa except A. multifida are restricted in distribution to the Rocky Mountains. A. multifida is a morphologically variable but cytologically homogeneous species widely distributed in both North and South America. The remaining taxa have biternate leaves and are sparingly represented in herbaria by specimens from widely separated localities. Their status has not been determined. A collection from Mt. Rainier, Wash., is diploid and one from Kittitas Co., Wash., is tetraploid.Karyotype studies indicate a close relationship among the tetraploids, A. multifida, A. tetonensis, and A. stylosa, all of which have one set of large and one set of small chromosomes. The other taxa have sets of small chromosomes only. Affinities among taxa in the A. lithophila and A. drummondii. complexes are suggested by the sharing of distinctive marker chromosomes. The European alpine A. baldensis L., 2n 16, is not related to the ternate-leaved taxa of the above complexes but a relationship with the biternate-leaved taxa may possibly exist.

scholarly journals Cranial osteology of the pampathere Holmesina floridanus (Xenarthra: Cingulata; Blancan NALMA), including a description of an isolated petrosal bone

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e4022 ◽  
Author(s):  
Timothy J. Gaudin ◽  
Lauren M. Lyon
Keyword(s):  
Natural History ◽  
South America ◽  
Phylogenetic Relationships ◽  
The Other ◽  
Cranial Morphology ◽  
Central Florida ◽  
Cranial Osteology ◽  
North And South America ◽  
North And South

The present study entails descriptions of several well-preserved skulls from the pampathere species Holmesina floridanus, recovered from Pliocene localities in central Florida and housed in the collections of the Florida Museum of Natural History. Bone by bone descriptions have allowed detailed reconstructions of cranial morphology. Cranial foramina are described and illustrated in detail, and their contents inferred. The first ever description of an isolated pampathere petrosal is also included. Cranial osteology of Holmesina floridanus is compared to that of Pleistocene species of Holmesina from both North and South America (Holmesina septentrionalis, Holmesina occidentalis), as well as to the other well-known pampathere genera, to closely related taxa among glyptodonts (Propalaehoplophorus), and to extinct and extant armadillos (Proeutatus, Euphractus). This study identifies a suite of apomorphic cranial features that serve to diagnose a putative, progressive series of more inclusive monophyletic groups, including the species Holmesina floridanus, the genus Holmesina, pampatheres, pampatheres plus glyptodonts, and a clade formed by pampatheres, glyptodonts, and Proeutatus. The study highlights the need for further anatomical investigations of pampathere cranial anatomy, especially those using modern scanning technology, and for analyses of pampathere phylogenetic relationships.

UX and E-Commerce

2021 ◽  
pp. 316-352
Author(s):  
Silvia Carter
Keyword(s):  
Best Practices ◽  
South America ◽  
Cultural Adaptation ◽  
The Other ◽  
Cross Border ◽  
Online Sales ◽  
The World ◽  
The One ◽  
North And South America ◽  
North And South

E-commerce is expected to see considerable growth in the next years anywhere all over the world. A trend that has been accelerated by the COVID-19. To succeed in this increasingly global and increasingly competitive landscape, e-commerce companies need to attract more and more traffic, the condition for getting clients. The questions “How important is UX for increasing the e-commerce sales?” and “Do geography and culture impact the UX performance?” are therefore essential. This chapter on the one hand analyzes the specific e-commerce UX elements and dimensions, and on the other hand compares strengths and weaknesses in Europe, Asia, Africa, North and South America to find UX international best practices. Keywords: Ecommerce, Online Sales, Cross-Border, International, Marketplaces, Geo-Cultural Adaptation, Ux Elements, Ux Dimensions, Worldwide, Global

IV.—The Geological Development, Descent and Distribution of the Mammalia

1893 ◽  
Vol 10 (9) ◽  
pp. 401-412 ◽  
Author(s):  
Karl A. von Zittel
Keyword(s):  
South America ◽  
The Past ◽  
Limited Experience ◽  
The World ◽  
Relationship Of ◽  
North And South America ◽  
The Relationship ◽  
North And South ◽  
Animal World

In a spirited treatise on the ‘Origin of our Animal World’ Prof. L. Rütimeyer, in the year 1867, described the geological development and distribution of the mammalia, and the relationship of the different faunas of the past with each other and with that now existing. Although, since the appearance of that masterly sketch the palæontological material has been, at least, doubled through new discoveries in Europe and more especially in North and South America, this unexpected increase has in most instances only served as a confirmation of the views which Rutimeyer advanced on more limited experience. At present, Africa forms the only great gap in our knowledge of the fossil mammalia; all the remaining parts of the world can show materials more or less abundantly, from which the course followed by the mammalia in their geological development can be traced with approximate certainty.

Transatlantic Radicalism

2021 ◽  
Keyword(s):  
South America ◽  
Atlantic Ocean ◽  
Case Studies ◽  
Individual Case ◽  
History Of ◽  
Late Nineteenth ◽  
Organizational Ties ◽  
North And South America ◽  
North And South ◽  
Political Radicalism

The Atlantic Ocean not only connected North and South America with Europe through trade but also provided the means for an exchange of knowledge and ideas, including political radicalism. Socialists and anarchists would use this “radical ocean” to escape state prosecution in their home countries and establish radical milieus abroad. However, this was often a rather unorganized development and therefore the connections that existed were quite diverse. The movement of individuals led to the establishment of organizational ties and the import and exchange of political publications between Europe and the Americas. The main aim of this book is to show how the transatlantic networks of political radicalism evolved with regard to socialist and anarchist milieus and in particular to look at the actors within the relevant processes—topics that have so far been neglected in the major histories of transnational political radicalism of the late nineteenth and early twentieth centuries. Individual case studies are examined within a wider context to show how networks were actually created, how they functioned and their impact on the broader history of the radical Atlantic.

scholarly journals Modelling tree ring cellulose <i>δ</i><sup>18</sup>O variations in two temperature-sensitive tree species from North and South America

2017 ◽  
Vol 13 (11) ◽  
pp. 1515-1526 ◽  
Author(s):  
Aliénor Lavergne ◽  
Fabio Gennaretti ◽  
Camille Risi ◽  
Valérie Daux ◽  
Etienne Boucher ◽  
...  
Keyword(s):  
South America ◽  
Isotopic Fractionation ◽  
Circulation Model ◽  
Effect Of Temperature ◽  
Temperature Sensitive ◽  
Nothofagus Pumilio ◽  
Climate Signal ◽  
North And South America ◽  
North And South ◽  
Two Temperature

Abstract. Oxygen isotopes in tree rings (δ18OTR) are widely used to reconstruct past climates. However, the complexity of climatic and biological processes controlling isotopic fractionation is not yet fully understood. Here, we use the MAIDENiso model to decipher the variability in δ18OTR of two temperature-sensitive species of relevant palaeoclimatological interest (Picea mariana and Nothofagus pumilio) and growing at cold high latitudes in North and South America. In this first modelling study on δ18OTR values in both northeastern Canada (53.86° N) and western Argentina (41.10° S), we specifically aim at (1) evaluating the predictive skill of MAIDENiso to simulate δ18OTR values, (2) identifying the physical processes controlling δ18OTR by mechanistic modelling and (3) defining the origin of the temperature signal recorded in the two species. Although the linear regression models used here to predict daily δ18O of precipitation (δ18OP) may need to be improved in the future, the resulting daily δ18OP values adequately reproduce observed (from weather stations) and simulated (by global circulation model) δ18OP series. The δ18OTR values of the two species are correctly simulated using the δ18OP estimation as MAIDENiso input, although some offset in mean δ18OTR levels is observed for the South American site. For both species, the variability in δ18OTR series is primarily linked to the effect of temperature on isotopic enrichment of the leaf water. We show that MAIDENiso is a powerful tool for investigating isotopic fractionation processes but that the lack of a denser isotope-enabled monitoring network recording oxygen fractionation in the soil–vegetation–atmosphere compartments limits our capacity to decipher the processes at play. This study proves that the eco-physiological modelling of δ18OTR values is necessary to interpret the recorded climate signal more reliably.

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