Ancient divergence and biogeography of Raukaua (Araliaceae) and close relatives in the southern hemisphere

2012 ◽  
Vol 25 (6) ◽  
pp. 432 ◽  
Author(s):  
Anthony Mitchell ◽  
Rong Li ◽  
Joseph W. Brown ◽  
Ines Schönberger ◽  
Jun Wen

Molecular genetic analyses were used to reconstruct phylogenetic relationships and estimate divergence times for Raukaua species and their close relatives. A monophyletic group identified as the ‘greater Raukaua clade’ was circumscribed, with eight representative species; its basal divergence was estimated at c. 70 Mya, possibly after Zealandia had separated from Gondwana. Raukaua is paraphyletic because of the placement of Motherwellia, Cephalaralia, Cheirodendron and Schefflera s.s. The phylogeny supports a more narrowly circumscribed Raukaua that includes the New Zealand but not the South American or Tasmanian representatives. Ancestors of the monophyletic South American and Tasmanian Raukaua and the mainland Australian Motherwellia and Cephalaralia diverged at c. 66 Mya and their current disjunction may be vicariant, with overland dispersal between Australia and South America, possibly via Antarctica. Vicariance is also a likely mechanism for divergence at c. 57 Mya of the monophyletic Motherwellia, Cephalaralia and Tasmanian Raukaua. The common ancestor of New Zealand Raukaua¸ Cheirodendron and Schefflera s.s. is inferred to have existed c. 62 Mya in New Zealand, before the marine incursions during the Oligocene, implying that New Zealand Raukaua and Schefflera s.s. survived the inundation period or speciated outside New Zealand and subsequently colonised. Ancestors of Cheirodendron split from New Zealand Raukaua c. 43 Mya and dispersed over vast expanses of the south-western Pacific to Hawaii.

2007 ◽  
Vol 85 (8) ◽  
pp. 731-745 ◽  
Author(s):  
Jun Wen ◽  
Ze-Long Nie ◽  
Akiko Soejima ◽  
Ying Meng

Phylogenetic analysis of 105 nuclear GAI1 sequences of Vitaceae provided a fairly robust phylogeny, largely congruent with the recently published chloroplast data of the family. In the GAI1 phylogeny, Cayratia Juss., Tetrastigma (Miq.) Planch., and Cyphostemma (Planch.) Alston form a clade. Cyphostemma and Tetrastigma are both monophyletic, and Cayratia is paraphyletic. Ampelopsis Michx is paraphyletic with the African Rhoicissus Planch. and the South American Cissus striata Ruiz & Pav. and its close relatives (e.g., Cissus simsiana Roem. & Schult.) nested within it. The pinnately leaved Ampelopsis forms a subclade, and the simple and palmately leaved Ampelopsis constitutes another subclade. All species of Cissus L. sampled from Asia, Africa, and Central and South America (except the C. striata complex) form a monophyletic group. Pterisanthes Blume of southeastern Asia forms a clade with the Asian Ampelocissus Planch. Vitis  L. is monophyletic and forms a larger clade with the tropical Ampelocissus and Pterisanthes . Parthenocissus Planch., forms a clade with Yua C.L. Li, with each genus reportedly monophyletic. Cissus from the Old World is paraphyletic with the neotropical core Cissus nested within it. The basal grade of Cissus consists of taxa from Africa. The African-Asian biogeographic relationships are complex, with several intercontinental disjunctions. The Northern Hemisphere Ampelopsis is most closely related to the South American C. striata complex and the African Rhoicissus .


2014 ◽  
Vol 29 (3) ◽  
pp. 315-330
Author(s):  
Yanina García Skabar ◽  
Matilde Nicolini

During the warm season 2002-2003, the South American Low-Level Jet Experiment (SALLJEX) was carried out in southeastern South America. Taking advantage of the unique database collected in the region, a set of analyses is generated for the SALLJEX period assimilating all available data. The spatial and temporal resolution of this new set of analyses is higher than that of analyses available up to present for southeastern South America. The aim of this paper is to determine the impact of assimilating data into initial fields on mesoscale forecasts in the region, using the Brazilian Regional Atmospheric Modeling System (BRAMS) with particular emphasis on the South American Low-Level Jet (SALLJ) structure and on rainfall forecasts. For most variables, using analyses with data assimilated as initial fields has positive effects on short term forecast. Such effect is greater in wind variables, but not significant in forecasts longer than 24 hours. In particular, data assimilation does not improve forecasts of 24-hour accumulated rainfall, but it has slight positive effects on accumulated rainfall between 6 and 12 forecast hours. As the main focus is on the representation of the SALLJ, the effect of data assimilation in its forecast was explored. Results show that SALLJ is fairly predictable however assimilating additional observation data has small impact on the forecast of SALLJ timing and intensity. The strength of the SALLJ is underestimated independently of data assimilation. However, Root mean square error (RMSE) and BIAS values reveal the positive effect of data assimilation up to 18-hours forecasts with a greater impact near higher topography.


Author(s):  
Mikhail Valer'evich Gorbachev

  This article discusses the political projects of civilizational level, which are designed and implemented in South America. The author examines MERCOSUR as the largest regional civilizational political project, its sociocultural foundation and institutional superstructure; functionality of the “core state” in formation and maintenance of the South American civilizational political project; problems of development and future implementation. The article reveals conflict potential of MERCOSUR, as well as sociocultural capabilities for its overcoming by the “core state” of the project. The research was conducted via application of civilizational-project methodology of interpretation of policy, which is based on methodological synthesis of the principles of project approach with provisions of the theory of civilizations. The author was able to determine the value grounds of MERCOSUR, which comprise its sociocultural foundation; identify the countries competing for status of the “core state” within the framework of this project. The nature of commonality between the key participants of the projects is identified. Problems and prospect of further development of MERCOSUR civilizational projects are defined.  


2021 ◽  
Author(s):  
Gonzalo Giribet ◽  
Kate Sheridan ◽  
Caitlin M. Baker ◽  
Christina J. Painting ◽  
Gregory I. Holwell ◽  
...  

The Opiliones family Neopilionidae is restricted to the terranes of the former temperate Gondwana: South America, Africa, Australia, New Caledonia and New Zealand. Despite decades of morphological study of this unique fauna, it has been difficult reconciling the classic species of the group (some described over a century ago) with recent cladistic morphological work and previous molecular work. Here we attempted to investigate the pattern and timing of diversification of Neopilionidae by sampling across the distribution range of the family and sequencing three markers commonly used in Sanger-based approaches (18S rRNA, 28S rRNA and cytochrome-c oxidase subunit I). We recovered a well-supported and stable clade including Ballarra (an Australian ballarrine) and the Enantiobuninae from South America, Australia, New Caledonia and New Zealand, but excluding Vibone (a ballarrine from South Africa). We further found a division between West and East Gondwana, with the South American Thrasychirus/Thrasychiroides always being sister group to an Australian–Zealandian (i.e. Australia + New Zealand + New Caledonia) clade. Resolution of the Australian–Zealandian taxa was analysis-dependent, but some analyses found Martensopsalis, from New Caledonia, as the sister group to an Australian–New Zealand clade. Likewise, the species from New Zealand formed a clade in some analyses, but Mangatangi often came out as a separate lineage from the remaining species. However, the Australian taxa never constituted a monophyletic group, with Ballarra always segregating from the remaining Australian species, which in turn constituted 1–3 clades, depending on the analysis. Our results identify several generic inconsistencies, including the possibility of Thrasychiroides nested within Thrasychirus, Forsteropsalis being paraphyletic with respect to Pantopsalis, and multiple lineages of Megalopsalis in Australia. In addition, the New Zealand Megalopsalis need generic reassignment: Megalopsalis triascuta will require its own genus and M. turneri is here transferred to Forsteropsalis, as Forsteropsalis turneri (Marples, 1944), comb. nov.


2008 ◽  
Vol 26 (11) ◽  
pp. 3457-3476 ◽  
Author(s):  
A. S. Taschetto ◽  
I. Wainer

Abstract. The Community Climate Model (CCM3) from the National Center for Atmospheric Research (NCAR) is used to investigate the effect of the South Atlantic sea surface temperature (SST) anomalies on interannual to decadal variability of South American precipitation. Two ensembles composed of multidecadal simulations forced with monthly SST data from the Hadley Centre for the period 1949 to 2001 are analysed. A statistical treatment based on signal-to-noise ratio and Empirical Orthogonal Functions (EOF) is applied to the ensembles in order to reduce the internal variability among the integrations. The ensemble treatment shows a spatial and temporal dependence of reproducibility. High degree of reproducibility is found in the tropics while the extratropics is apparently less reproducible. Austral autumn (MAM) and spring (SON) precipitation appears to be more reproducible over the South America-South Atlantic region than the summer (DJF) and winter (JJA) rainfall. While the Inter-tropical Convergence Zone (ITCZ) region is dominated by external variance, the South Atlantic Convergence Zone (SACZ) over South America is predominantly determined by internal variance, which makes it a difficult phenomenon to predict. Alternatively, the SACZ over western South Atlantic appears to be more sensitive to the subtropical SST anomalies than over the continent. An attempt is made to separate the atmospheric response forced by the South Atlantic SST anomalies from that associated with the El Niño – Southern Oscillation (ENSO). Results show that both the South Atlantic and Pacific SSTs modulate the intensity and position of the SACZ during DJF. Particularly, the subtropical South Atlantic SSTs are more important than ENSO in determining the position of the SACZ over the southeast Brazilian coast during DJF. On the other hand, the ENSO signal seems to influence the intensity of the SACZ not only in DJF but especially its oceanic branch during MAM. Both local and remote influences, however, are confounded by the large internal variance in the region. During MAM and JJA, the South Atlantic SST anomalies affect the magnitude and the meridional displacement of the ITCZ. In JJA, the ENSO has relatively little influence on the interannual variability of the simulated rainfall. During SON, however, the ENSO seems to counteract the effect of the subtropical South Atlantic SST variations on convection over South America.


Zootaxa ◽  
2020 ◽  
Vol 4751 (1) ◽  
pp. 75-104
Author(s):  
MAURICIO M. ROCHA ◽  
ELIANA M. CANCELLO

In this contribution we present updates on the taxonomy and morphology of the South American species of Amitermes. Two new species are described: Amitermes bandeirai, sp. n., from Brazil, and Amitermes lilloi, sp. n., from Argentina. Amitermes nordestinus is a junior synonym of Amitermes aporema. The imago of A. aporema is described for the first time. Detailed comparative gut anatomy of the eight species is presented for the first time. The geographic distribution of Amitermes in South America is expanded and the distribution patterns of some species are discussed. 


Author(s):  
José Soares Ferreira Neto

In general, European and North American countries, as well as Australia and New Zealand, have already eradicated or reached good levels of control of brucellosis and tuberculosis in cattle. In the rest of the world, however, the epidemiological situation of these two diseases is frequently poorly understood. In this review article, quantified data on these diseases in the South American countries are presented. Initially, the aspects that led the continent to host 25% of the world cattle population are presented, in addition to the aspects that placed the continent at a prominent position in the international meat market. Subsequently the continent was divided into three country groups, considering the size of the cattle population and how well the epidemiological situation of brucellosis and tuberculosis in cattle is quantified. It is argued that countries that do not generate high-quality quantitative epidemiological data on these diseases have serious limitations in outlining and managing control or eradication strategies. Thus, for successful outcomes, at least methodologies to estimate the prevalence of infected herds should be employed.


2015 ◽  
Vol 89 (6) ◽  
pp. 956-965 ◽  
Author(s):  
Leandro M. Pérez ◽  
Juan López-Gappa ◽  
Miguel Griffin

AbstractThe bryozoan fauna from the South American Cenozoic is poorly known. The study of new material collected in the Monte León Formation (early Miocene), gave us the opportunity to describe four new species: Valdemunitella canui n. sp., Foveolaria praecursor n. sp., Neothoa reptans n. sp., and Calyptotheca santacruzana n. sp. Two of them (V. canui and C. santacruzana) were first recorded by F. Canu and interpreted as recent species from the Australian bryozoan fauna, but are herein described as new species. The stratigraphic range of Otionella parvula (Canu, 1904) is extended to the early Miocene. The present study emphasizes the close relationships between the South American Neogene bryozoan faunas and those of other Gondwanan sub-continents such as New Zealand and Australia.


Quaternary ◽  
2019 ◽  
Vol 2 (1) ◽  
pp. 6 ◽  
Author(s):  
Michael Deininger ◽  
Brittany Marie Ward ◽  
Valdir F. Novello ◽  
Francisco W. Cruz

Here we present an overview of speleothem δ18O records from South America, most of which are available in the Speleothem Isotopes Synthesis and Analysis (SISAL_v1) database. South American tropical and subtropical speleothem δ18O time series are primarily interpreted to reflect changes in precipitation amount, the amount effect, and consequently history of convection intensity variability of convergence zones such as the Intertropical Convergence Zone (ITCZ) and the South America Monsoon System (SAMS). We investigate past hydroclimate scenarios in South America related to the South American Monsoon System in three different time periods: Late Pleistocene, Holocene, and the last two millennia. Precession driven summertime insolation is the main driver of convective variability over the continent during the last 120 kyrs (from present day to 120 kyrs BP), including the Holocene. However, there is a dipole between speleothem δ18O records from western and eastern South America. Records located in the central region of Brazil are weakly affected by insolation-driven variability, and instead are more susceptible to the variability associated with the South Atlantic Convergence Zone (SACZ). Cold episodic events in the Northern Hemisphere, such as Heinrich and Bond Events, and the Little Ice Age, increase the convective activity of the SAMS, resulting in increased precipitation amount in South America.


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