scholarly journals The adaptive challenge of extreme conditions shapes evolutionary diversity of plant assemblages at continental scales

2021 ◽  
Vol 118 (37) ◽  
pp. e2021132118
Author(s):  
Danilo M. Neves ◽  
Andrew J. Kerkhoff ◽  
Susy Echeverría-Londoño ◽  
Cory Merow ◽  
Naia Morueta-Holme ◽  
...  
Keyword(s):  
Biological Diversity ◽  
Physiological Stress ◽  
Arid Environments ◽  
Tropical Environments ◽  
Diversity Gradients ◽  
Wet Tropics ◽  
Plant Assemblages ◽  
Temperate Mixed Forests ◽  
North And South America ◽  
North And South

The tropical conservatism hypothesis (TCH) posits that the latitudinal gradient in biological diversity arises because most extant clades of animals and plants originated when tropical environments were more widespread and because the colonization of colder and more seasonal temperate environments is limited by the phylogenetically conserved environmental tolerances of these tropical clades. Recent studies have claimed support of the TCH, indicating that temperate plant diversity stems from a few more recently derived lineages that are nested within tropical clades, with the colonization of the temperate zone being associated with key adaptations to survive colder temperatures and regular freezing. Drought, however, is an additional physiological stress that could shape diversity gradients. Here, we evaluate patterns of evolutionary diversity in plant assemblages spanning the full extent of climatic gradients in North and South America. We find that in both hemispheres, extratropical dry biomes house the lowest evolutionary diversity, while tropical moist forests and many temperate mixed forests harbor the highest. Together, our results support a more nuanced view of the TCH, with environments that are radically different from the ancestral niche of angiosperms having limited, phylogenetically clustered diversity relative to environments that show lower levels of deviation from this niche. Thus, we argue that ongoing expansion of arid environments is likely to entail higher loss of evolutionary diversity not just in the wet tropics but in many extratropical moist regions as well.

scholarly journals Mitogenome analyses elucidate the evolutionary relationships of a probable Eocene wet tropics relic in the xerophilic lizard genus Acanthodactylus

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sebastian Kirchhof ◽  
Mariana L. Lyra ◽  
Ariel Rodríguez ◽  
Ivan Ineich ◽  
Johannes Müller ◽  
...  
Keyword(s):  
Species Turnover ◽  
Arid Environments ◽  
Environmental Niche ◽  
Basal Node ◽  
Tropical Environments ◽  
Long Time ◽  
Wet Tropics ◽  
Sub Saharan ◽  
Environmental Niche Models ◽  
Archival Dna

AbstractClimate has a large impact on diversity and evolution of the world’s biota. The Eocene–Oligocene transition from tropical climate to cooler, drier environments was accompanied by global species turnover. A large number of Old World lacertid lizard lineages have diversified after the Eocene–Oligocene boundary. One of the most speciose reptile genera in the arid Palearctic, Acanthodactylus, contains two sub-Saharan species with unresolved phylogenetic relationship and unknown climatic preferences. We here aim to understand how and when adaptation to arid conditions occurred in Acanthodactylus and when tropical habitats where entered. Using whole mitogenomes from fresh and archival DNA and published sequences we recovered a well-supported Acanthodactylus phylogeny and underpinned the timing of diversification with environmental niche analyses of the sub-Saharan species A. guineensis and A. boueti in comparison to all arid Acanthodactylus. We found that A. guineensis represents an old lineage that splits from a basal node in the Western clade, and A. boueti is a derived lineage and probably not its sister. Their long branches characterize them—and especially A. guineensis—as lineages that may have persisted for a long time without further diversification or have undergone multiple extinctions. Environmental niche models verified the occurrence of A. guineensis and A. boueti in hot humid environments different from the other 42 arid Acanthodactylus species. While A. guineensis probably remained in tropical habitat from periods prior to the Eocene–Oligocene boundary, A. boueti entered tropical environments independently at a later period. Our results provide an important baseline for studying adaptation and the transition from humid to arid environments in Lacertidae.

Gerald H. Thayer's ornithological work in St Vincent and the Grenadines, Lesser Antilles

2018 ◽  
Vol 45 (1) ◽  
pp. 21-39 ◽  
Author(s):  
James W. Wiley
Keyword(s):  
New York ◽  
New York City ◽  
West Indies ◽  
The United States ◽  
Lesser Antilles ◽  
American Museum ◽  
The West ◽  
Comparative Zoology ◽  
North And South America ◽  
North And South

Gerald Handerson Thayer (1883–1939) was an artist, writer and naturalist who worked in North and South America, Europe and the West Indies. In the Lesser Antilles, Thayer made substantial contributions to the knowledge and conservation of birds in St Vincent and the Grenadines. Thayer observed and collected birds throughout much of St Vincent and on many of the Grenadines from January 1924 through to December 1925. Although he produced a preliminary manuscript containing interesting distributional notes and which is an early record of the region's ornithology, Thayer never published the results of his work in the islands. Some 413 bird and bird egg specimens have survived from his work in St Vincent and the Grenadines and are now housed in the American Museum of Natural History (New York City) and the Museum of Comparative Zoology (Cambridge, Massachusetts). Four hundred and fifty eight specimens of birds and eggs collected by Gerald and his father, Abbott, from other countries are held in museums in the United States.

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.

Richard Francis Burton

2021 ◽  
Keyword(s):  
East India Company ◽  
East African ◽  
British Imperialism ◽  
Prolific Author ◽  
Arabian Nights ◽  
Sexually Explicit ◽  
Volume Translation ◽  
North And South America ◽  
North And South ◽  
Kama Sutra

Richard Francis Burton (b. 1821–d. 1890) was a prodigiously gifted polymath who knew some twenty-five languages, wrote more than twenty books about his journeys through distant lands, introduced the Kama Sutra and other exotic works of erotica to English readers, and produced a controversial and influential sixteen-volume translation of the Arabian Nights. Few Victorians ventured to as many regions of the world as Burton or showed as much curiosity as he did about the cultures and customs of the peoples who inhabited them. He was raised by his expatriate parents in Italy and France, began his career as a cadet in the East India Company army, gained fame from his pilgrimage to Mecca disguised as a Muslim from South Asia, led the first British-sponsored expedition in search of the source of the Nile River, traveled extensively through East and West Africa, North and South America, Arabia and even Iceland, and spent the final decades of his life as a British consul in Damascus and Trieste. He was a prominent figure in bohemian circles in mid-century London, where he helped found the controversial Anthropological Society and the notorious Cannibal Club; he provoked public outrage for his defense of Islam, polygamy, and slavery; he famously and tragically clashed with John Hanning Speke, his erstwhile companion on the East African expedition, over the latter’s claims to have discovered the Nile’s source; he spent the last decade of his life battling the forces of prudery in Britain with his translations of The Kama Sutra, The Book of a Thousand Nights and Night (especially its “Terminal Essay” on pederasty), and other sexually explicit works. He was both an agent and a critic of British imperialism, a racist and a relativist, a religious skeptic and a spiritualist, a pornographer and a cultural provocateur, a man of action and a prolific author. No wonder he has attracted the attention of biographers and literary scholars, historians and cultural critics, geographers and anthropologists, area studies specialists, novelists and many others. They have been drawn to his protean character, his literary accomplishments, his contrarian opinions, his daring expeditions, his geographical findings, his ethnographic observations, his interest in human sexuality, and much more. Every generation, it seems, has found new reasons to revisit his life and writings.

The Edinburgh Companion to Virginia Woolf and Contemporary Global Literature

2020 ◽  
Keyword(s):  
Virginia Woolf ◽  
Pacific Islands ◽  
The United States ◽  
Global Studies ◽  
East Europe ◽  
The Pacific ◽  
The World ◽  
North And South America ◽  
Multiple Languages ◽  
North And South

This book considers the global responses Woolf’s work has inspired and her worldwide impact. The 23 chapters address the ways Woolf is received by writers, publishers, academics, reading audiences, and students in countries around the world; how she is translated into multiple languages; and how her life is transformed into global contemporary biofiction. The 24 authors hail from regions around the world: West and East Europe, the Middle East/North Africa, North and South America, East Asia and the Pacific Islands. They write about Woolf’s reception in Ireland, France, Italy, Germany, Poland, Estonia, Russia, Egypt, Kenya, Mexico, Argentina, Uruguay, Brazil, the United States, China, Japan and Australia. The Edinburgh Companion is dialogic and comparative, incorporating both transnational and local tendencies insofar as they epitomise Woolf’s global reception and legacy. It contests the ‘centre’ and ‘periphery’ binary, offering new models for Woolf global studies and promoting cross-cultural understandings.

Beneficial Effects of Liposomal Formulations of Lichen Substances: A Review

2021 ◽  
Vol 18 ◽  
Author(s):  
Vinay Bharadwaj Tatipamula ◽  
Ha Thi Nguyen ◽  
Biljana Kukavica
Keyword(s):  
Substantial Improvement ◽  
Traditional Medicines ◽  
Beneficial Effects ◽  
Liposomal Formulations ◽  
Lichen Substances ◽  
Potential Applications ◽  
Lichen Metabolites ◽  
North And South America ◽  
North And South ◽  
Low Solubility

: Lichens are commonly used as essential traditional medicines to treat various conditions, including skin disorders, wounds, digestive, respiratory, obstetric, and gynecological problems in many cultures in Africa, Asia, Europe, Haitian, Oceania, and North and South America. Lichens have been deeply investigated for their phytochemical properties, and to date, numerous compounds (also known as substances) have been successfully isolated from the extracts. However, the low solubility and bioavailability of pure lichen substances have been widely recognized as the significant issues hindering their biological applications. Recently, several groups have investigated the properties and the potential applications of lichen metabolites-based liposomal formulations and revealed a substantial improvement in their solubility, bioactivity, and toxicity in the animal. Thus, in this topical review, we aimed to provide an overview of liposomal structures, the efficacy of liposomal formulations, as well as their beneficial effects as compared to the free compounds themselves.

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 Mercury distribution in the upper troposphere and lower most stratosphere according to measurements by the IAGOS-CARIBIC observatory, 2014–2016

2018 ◽  
Author(s):  
Franz Slemr ◽  
Andreas Weigelt ◽  
Ralf Ebinghaus ◽  
Johannes Bieser ◽  
Carl A. M. Brenninkmeijer ◽  
...  
Keyword(s):  
Large Scale ◽  
Total Mercury ◽  
Trace Gases ◽  
Boreal Winter ◽  
Signal Integration ◽  
Upper Troposphere ◽  
Cloud Scavenging ◽  
Passenger Aircraft ◽  
North And South America ◽  
North And South

Abstract. Mercury was measured onboard the IAGOS-CARIBIC passenger aircraft since May 2005 until February 2016 during nearly monthly sequences of mostly four intercontinental flights from Germany to destinations in North and South America, Africa, and South and East Asia. Most of these mercury data were obtained using an internal default signal integration procedure of the Tekran instrument but since April 2014 more precise and accurate data were obtained using post-flight manual integration of the instrument raw signal. In this paper we use the latter data. Elevated upper tropospheric total mercury (TM) concentrations due to large scale biomass burning were observed in the upper troposphere (UT) at the equator and southern latitudes during the flights to Latin America and South Africa in boreal autumn (SON) and boreal winter (DJF). TM concentrations in the lowermost stratosphere (LMS) decrease with altitude above the thermal tropopause but the gradient is less steep than reported before. Seasonal variation of the vertical TM distribution in the UT and LMS is similar to that of other trace gases with surface sources and stratospheric sinks. Using speciation experiments, we show that nearly identical TM and gaseous elementary mercury (GEM) concentrations exist at and below the tropopause. Above the thermal tropopause GEM concentrations are almost always smaller than those of TM and the TM – GEM (i.e. Hg2+) difference increases up to ~ 40 % of TM at ~ 2 km and more above the thermal tropopause. Correlations with N2O as a reference tracer suggest stratospheric lifetimes of 72 ± 37 and 74 ± 27 yr for TM and GEM, respectively, comparable to the stratospheric lifetime of COS. This coincidence, combined with pieces of evidence from us and other researchers, corroborates the hypothesis that Hg2+ formed by oxidation in the stratosphere attaches to sulfate particles formed mainly by oxidation of COS and is removed with them from the stratosphere by air mass exchange, gravitational sedimentation, and cloud scavenging processes.

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