scholarly journals Multiple incursion pathways for Helicoverpa armigera in Brazil show its genetic diversity spreading in a connected world

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Jonas Andre Arnemann ◽  
Stephen Roxburgh ◽  
Tom Walsh ◽  
Jerson Guedes ◽  
Karl Gordon ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Gene Flow ◽  
South America ◽  
New World ◽  
Flow Patterns ◽  
South American ◽  
Southern Brazil ◽  
American Continent ◽  
Central Brazil ◽  
South American Continent

AbstractThe Old World cotton bollworm Helicoverpa armigera was first detected in Brazil with subsequent reports from Paraguay, Argentina, Bolivia, and Uruguay. This pattern suggests that the H. armigera spread across the South American continent following incursions into northern/central Brazil, however, this hypothesis has not been tested. Here we compare northern and central Brazilian H. armigera mtDNA COI haplotypes with those from southern Brazil, Uruguay, Argentina, and Paraguay. We infer spatial genetic and gene flow patterns of this dispersive pest in the agricultural landscape of South America. We show that the spatial distribution of H. armigera mtDNA haplotypes and its inferred gene flow patterns in the southwestern region of South America exhibited signatures inconsistent with a single incursion hypothesis. Simulations on spatial distribution patterns show that the detection of rare and/or the absence of dominant mtDNA haplotypes in southern H. armigera populations are inconsistent with genetic signatures observed in northern and central Brazil. Incursions of H. armigera into the New World are therefore likely to have involved independent events in northern/central Brazil, and southern Brazil/Uruguay-Argentina-Paraguay. This study demonstrates the significant biosecurity challenges facing the South American continent, and highlights alternate pathways for introductions of alien species into the New World.

scholarly journals Multiple incursion pathways for Helicoverpa armigera in Brazil show its genetic diversity spreading in a connected world

2019 ◽  
Author(s):  
Jonas A. Arnemann ◽  
Stephen H. Roxburgh ◽  
Tom Walsh ◽  
Jerson V.C. Guedes ◽  
Karl H.J. Gordon ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Gene Flow ◽  
South America ◽  
New World ◽  
Flow Patterns ◽  
South American ◽  
Southern Brazil ◽  
American Continent ◽  
Central Brazil ◽  
South American Continent

AbstractThe Old World cotton bollworm Helicoverpa armigera was first detected in Brazil with subsequent reports from Paraguay, Argentina, Bolivia, and Uruguay. This pattern suggests that the H. armigera spread across the South American continent following incursions into northern/central Brazil, however, this hypothesis has not been tested. Here we compare northern and central Brazilian H. armigera mtDNA COI haplotypes with those from southern Brazil, Uruguay, Argentina, and Paraguay. We infer spatial genetic and gene flow patterns of this dispersive pest in the agricultural landscape of South America. We show that the spatial distribution of H. armigera mtDNA haplotypes and its inferred gene flow patterns in the southwestern region of South America exhibited signatures inconsistent with a single incursion hypothesis. Simulations on spatial distribution patterns show that the detection of rare and/or the absence of dominant mtDNA haplotypes in southern H. armigera populations are inconsistent with genetic signatures observed in northern and central Brazil. Incursions of H. armigera into the New World are therefore likely to have involved independent events in northern/central Brazil, and southern Brazil/Uruguay-Argentina-Paraguay. This study demonstrates the significant biosecurity challenges facing the South American continent, and highlights alternate pathways for introductions of alien species into the New World.

scholarly journals Arrival and diversification of mabuyine skinks (Squamata: Scincidae) in the Neotropics based on a fossil-calibrated timetree

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3194 ◽  
Author(s):  
Anieli Guirro Pereira ◽  
Carlos G. Schrago
Keyword(s):  
South America ◽  
New World ◽  
Phenotypic Traits ◽  
South American ◽  
Ancestral State ◽  
American Continent ◽  
The South ◽  
Diversification Rates ◽  
Mode Of Reproduction ◽  
South American Continent

BackgroundThe evolution of South American Mabuyinae skinks holds significant biogeographic interest because its sister lineage is distributed across the African continent and adjacent islands. Moreover, at least one insular species,Trachylepis atlantica, has independently reached the New World through transoceanic dispersal. To clarify the evolutionary history of both Neotropical lineages, this study aimed to infer an updated timescale using the largest species and gene sampling dataset ever assembled for this group. By extending the analysis to the Scincidae family, we could employ fossil information to estimate mabuyinae divergence times and carried out a formal statistical biogeography analysis. To unveil macroevolutionary patterns, we also inferred diversification rates for this lineage and evaluated whether the colonization of South American continent significantly altered the mode of Mabuyinae evolution.MethodsA time-calibrated phylogeny was inferred under the Bayesian framework employing fossil information. This timetree was used to (i) evaluate the historical biogeography of mabuiyines using the statistical approach implemented in BioGeoBEARS; (ii) estimate macroevolutionary diversification rates of the South American Mabuyinae lineages and the patterns of evolution of selected traits, namely, the mode of reproduction, body mass and snout–vent length; (iii) test the hypothesis of differential macroevolutionary patterns in South American lineages in BAMM and GeoSSE; and (iv) re-evaluate the ancestral state of the mode of reproduction of mabuyines.ResultsOur results corroborated the hypothesis that the occupation of the South American continent by Mabuyinae consisted of two independent dispersion events that occurred between the Oligocene and the Miocene. We found significant differences in speciation rates between the New World and the remaining Mabuyinae clades only in GeoSSE. The influence of phenotypic traits on diversification rates was not supported by any method. Ancestral state reconstruction suggested that the ancestor of South American mabuyine was likely viviparous.DiscussionOur analyses further corroborated the existence of a transoceanic connection between Africa and South America in the Eocene/Oligocene period (Atlantogea). Following colonization of the isolated South America and subsequent dispersal through the continent by the ancestral mabuyine stock, we detected no difference in macroevolutionary regimes of New World clades. This finding argued against the ecological opportunity model as an explanation for the diversity of living mabuyines.

Darwin's Early Notes on Coral Reef Formation

1984 ◽  
Vol 3 (2) ◽  
pp. 160-163 ◽  
Author(s):  
Frederick Burkhardt
Keyword(s):  
Coral Reef ◽  
South America ◽  
Point Of View ◽  
South American ◽  
American Continent ◽  
The Pacific ◽  
The Pacific Ocean ◽  
South American Continent ◽  
Reef Formation ◽  
Water Coral

Darwin's letters and some rough notes found in his field notebooks of 1835 confirm the statement in his Autobiography that he had formulated his theory of coral reef formation before the Beagle left South America and before he had seen a coral reef. His geological observations having convinced him of the elevation of the South American continent, Darwin predicted that evidence of a compensatory gradual subsidence of the Pacific Ocean floor would be found in the existence of shallow-water coral genera in the Pacific reef formations. The first draft of the theory was written on board the Beagle shortly after seeing the reefs of Moorea in November 1835. After visiting the Cocos (Keeling) Islands he wrote a summary of his view in a letter of April 1838, in which he expressed his conviction that he had found an explanation which would "put some of the facts in a more simple and connected point of view, than that in which they have hitherto been considered".

A BOUGUER GRAVITY ANOMALY MAP OF SOUTH AMERICA

Geophysics ◽  
1975 ◽  
Vol 40 (1) ◽  
pp. 120-120
Author(s):  
Gerald L. Breville
Keyword(s):  
South America ◽  
Gravity Anomaly ◽  
South American ◽  
Bouguer Gravity ◽  
American Continent ◽  
Technical Paper ◽  
Bouguer Gravity Anomaly ◽  
Anomaly Map ◽  
South American Continent

A recently prepared Bouguer gravity anomaly map of South America is the first gravity anomaly representation of the entire South American continent. The technical paper which accompanies the map was presented by Breville et al. (1973). A copy of the map and technical paper may be obtained by writing for DMAAC Technical Paper No. 73-2 to the following address: Director, DMA Aerospace Center, ATTN: RDN, South Annex, St. Louis AFS, Mo 63125.

Israeli penetration in South America (1973-1947)

2021 ◽  
Vol 26 ◽  
pp. 1-23
Keyword(s):  
South America ◽  
Key Words ◽  
Decision Makers ◽  
The Political ◽  
South American ◽  
American Continent ◽  
The South ◽  
Political Decision ◽  
South American Continent

This research is an attempt to uncover the reality and method of Israeli penetration in the South American continent, and aims to draw attention to the weaknesses and mistakes in the role of Arab communities that they had to play in South America, and the position of Arab governments towards that continent. The research was divided into two main axes, as the first dealt with the means of Israeli penetration in South America until 1947, providing a brief overview of the roots of the penetration in the South American continent and the methods it adopted in achieving this. While the second axis focused on the stance of the South American countries on the Arab-Israeli conflict (1947-1973). However, the Israeli infiltration was affecting the political decision-makers in that continent towards the decision to partition Palestine up to the October 1973 war. Key words: the penetration, Palestine, Israel, immigration, Arabs, America

Species diversity and distributions of microdrile earthworms (Annelida, Clitellata, Enchytraeidae) from South America

Zootaxa ◽  
2009 ◽  
Vol 2065 (1) ◽  
pp. 51-68 ◽  
Author(s):  
MARTIN L. CHRISTOFFERSEN
Keyword(s):  
South America ◽  
Sister Group ◽  
Lateral Position ◽  
Nominal Species ◽  
South American ◽  
Dorsal Vessel ◽  
American Continent ◽  
Northeast Region ◽  
Biodiversity Database ◽  
South American Continent

A comprehensive biodiversity database of Enchytraeidae produced 66 nominal species reported to date from South America (Achaeta, 6 species; Buchholzia, 1; Cognettia, 1; Enchytraeus, 3; Fridericia, 5; Grania, 1; Guaranidrilus, 10; Hemienchytraeus, 12; Henlea, 2; Lumbricillus, 7; Marionina, 12; Stephensoniella, 1; Timmodrilus, 1; Tupidrilus, 4). Almost 76% of this fauna (50 species) is endemic to the South American continent. The remaining 16 species are more or less largely distributed. Detailed South American occurrences are provided. This is the first reassessment of South American enchytraeids in 27 years. The group is conspicuoulsy absent from the northeast region of Brazil. Enchytraeidae are microdrile earthworms, representing the sister group of the Crassiclitellata, or megadrile earthworms. This relationship is supported by molecular phylogenies, ontogenetic transformations, ecological evidence, and several morphological synapomorphies (dorsal pores, contractil dorsal vessel, lateral position of dorsal chaetal bundles, and shape of chaetae).

Eocene birds from the western margin of southernmost South America

2010 ◽  
Vol 84 (6) ◽  
pp. 1061-1070 ◽  
Author(s):  
Michel A. Sallaberry ◽  
Roberto E. Yury-Yáñez ◽  
Rodrigo A. Otero ◽  
Sergio Soto-Acuña ◽  
Teresa G. Torres
Keyword(s):  
South America ◽  
Southern Hemisphere ◽  
First Record ◽  
South American ◽  
American Continent ◽  
Western Margin ◽  
Geological Units ◽  
South American Continent ◽  
Previous Assumption ◽  
Seymour Island

This study presents the first record of Eocene birds from the western margin of southernmost South America. Three localities in Magallanes, southern Chile, have yielded a total of eleven bird remains, including Sphenisciformes (penguins) and one record tentatively assigned to cf. Ardeidae (egrets). Two different groups of penguins have been recognized from these localities. The first group is similar in size to the smallest taxa previously described from Seymour Island, Marambiornis Myrcha et al., 2002, Mesetaornis Myrcha et al., 2002, and Delphinornis Wiman, 1905. The second recognized group is similar in size to the biggest taxa from Seymour Island; based on the available remains, we recognize the genus Palaeeudyptes Huxley, 1859, one of the most widespread penguin genera in the Southern Hemisphere during the Eocene. The stratigraphic context of the localities indicates a certain level of correlation with the geological units described on Seymour Island. The newly studied materials cast more light on the paleobiogeography of the group, extending the known ranges to the South American continent. In addition to the newly discovered birds, the presence of several taxa of elasmobranchs previously recovered exclusively from Eocene beds in the Southern Hemisphere help to clarify the age of the studied localities, widely discussed during the last decades. This paper verifies the presence of extensive Eocene sedimentary successions with fossil vertebrates along the western margin of southern South America, contrary to the previous assumption that such a record is lacking in Chile.

scholarly journals Subpolar High Anomaly Preconditioning Precipitation over South America

2010 ◽  
Vol 67 (5) ◽  
pp. 1526-1542 ◽  
Author(s):  
Silvina A. Solman ◽  
Isidoro Orlanski
Keyword(s):  
Pacific Ocean ◽  
South America ◽  
Rossby Wave ◽  
South American ◽  
American Continent ◽  
The South ◽  
South Pacific Ocean ◽  
Anomalous Circulation ◽  
Frontal Activity ◽  
South American Continent

Abstract The mechanisms associated with the intraseasonal variability of precipitation over South America during the spring season are investigated with emphasis on the influence of a quasi-stationary anomalous circulation over the southeastern South Pacific Ocean (SEP). A spectral analysis performed to the bandpass-filtered time series of daily precipitation anomalies for the La Plata Basin (LPB) and the South Atlantic convergence zone (SACZ) regions revealed several statistically relevant peaks corresponding to periods of roughly 23 days and 14–16 days—with the lower (higher) frequency peaks more prevalent for the SACZ (LPB). The large-scale circulation patterns preconditioning precipitation variability over both regions were explored by means of a regression analysis performed on the daily 500-hPa geopotential anomaly field provided by the NCEP–NCAR reanalysis dataset. The most prominent feature of the regression fields is the presence of a quasi-stationary anomalous anticyclonic (cyclonic) circulation over the southeastern South Pacific Ocean associated with positive rainfall anomalies over the LPB (SACZ) and, emanating from that high (low), an external Rossby wave propagating northeastward toward the South American continent. The synoptic-scale activity, quantified in terms of a frontal activity index, showed a strong influence on precipitation over the LPB and to a lesser extent over the SACZ. Moreover, the frontal activity is actually modulated by the anomalous high circulation over the SEP region. The behavior of this anomalous circulation may be supported by a positive feedback mechanism that can enhance the response of the high anomaly itself, which in turns reinforces the Rossby wave train propagating toward the South American continent.

scholarly journals First Record of an Anthurid Isopod, Cyathura Univam sp. n., on the South American Continent

1983 ◽  
Vol 53 (2) ◽  
pp. 247-254 ◽  
Author(s):  
Lazare Botosaneanu
Keyword(s):  
South America ◽  
First Record ◽  
The Other ◽  
South American ◽  
American Continent ◽  
The South ◽  
South American Continent

Description of Cyathura univam sp. n. (Isopoda: Anthuridea), a depigmented and eyeless species from oligohaline cave water, at Mayorquines (Peninsula de Morocoy, Venezuela). This is the first species of the suborder to be found in South America. It is related to two stygobiont species, one from Curaçao and the other from Aruba.

scholarly journals A Novel Hepacivirus in Wild Rodents from South America

Viruses ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 297 ◽  
Author(s):  
William de Souza ◽  
Marcílio Fumagalli ◽  
Gilberto Sabino-Santos ◽  
Felipe Motta Maia ◽  
Sejal Modha ◽  
...  
Keyword(s):  
South America ◽  
Molecular Detection ◽  
South American ◽  
American Continent ◽  
Wild Rodents ◽  
Rt Pcr ◽  
Paulo State ◽  
The Family ◽  
Positive Sense ◽  
South American Continent

The Hepacivirus genus comprises single-stranded positive-sense RNA viruses within the family Flaviviridae. Several hepaciviruses have been identified in different mammals, including multiple rodent species in Africa, Asia, Europe, and North America. To date, no rodent hepacivirus has been identified in the South American continent. Here, we describe an unknown hepacivirus discovered during a metagenomic screen in Akodon montensis, Calomys tener, Oligoryzomys nigripes, Necromys lasiurus, and Mus musculus from São Paulo State, Brazil. Molecular detection of this novel hepacivirus by RT-PCR showed a frequency of 11.11% (2/18) in Oligoryzomys nigripes. This is the first identification of hepavivirus in sigmondonine rodents and in rodents from South America. In sum, our results expand the host range, viral diversity, and geographical distribution of the Hepacivirus genus.

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