scholarly journals Phylogenetic Relationships Among Some Neotropical Parrot Genera (Psittacidae) Based on Mitochondrial Sequences

The Auk ◽  
2004 ◽  
Vol 121 (1) ◽  
pp. 230-242
Author(s):  
Erika S. Tavares ◽  
Carlos Yamashita ◽  
Cristina Y. Miyaki
Keyword(s):  
South America ◽  
Cytochrome Oxidase ◽  
Control Region ◽  
Phylogenetic Relationships ◽  
New World ◽  
Environmental Changes ◽  
Phylogenetic Study ◽  
Mitochondrial Sequences ◽  
And Control ◽  
Ribosomal Dnas

Abstract The New World tribe Arini includes 30 genera and represents 148 known species of parrots. A previous phylogenetic study examined nine of those genera and suggested the existence of two groups. Our objective was to better understand the relationships among 14 species from 9 genera belonging to one of those groups. We partially sequenced the 12S and 16S ribosomal DNAs, cytochrome b, cytochrome oxidase I, and control region. We improved our understanding of the phylogenetic relationships among Neotropical parrots by adding both taxa and sequences, but the relationships among the deeper lineages were not well resolved. Our results agree with present classifications that place some species formerly in the genus Ara into three additional genera (Primolius, Orthopsittaca, and Diopsittaca). Additionally, we suggest that (1) D. nobilis and Guarouba guarouba are closely related and the genus Aratinga is not monophyletic; (2) diversification of genera may have occurred during the Miocene, and of species within genera during the Pliocene and Pleistocene; and (3) geologic, climatic, and environmental changes in South America may have been related to that diversification.

Systematics and biogeography of Salina MacGillivray (Collembola: Entomobryoidea), with emphasis on the species groups in the New World

2020 ◽  
Vol 51 (1) ◽  
pp. 81-138
Author(s):  
Fábio G.L. Oliveira ◽  
Nikolas G. Cipola ◽  
Eduardo A.B. Almeida
Keyword(s):  
New Species ◽  
South America ◽  
Phylogenetic Relationships ◽  
New World ◽  
Morphological Character ◽  
Morphological Characters ◽  
Neotropical Species ◽  
Species Groups ◽  
First Time ◽  
Group Distribution

Nine new species of the collembolan genus Salina MacGillivray from South America are described and illustrated. Two Neotropical species were recorded for the first time from Brazil: S. dedoris Mari-Mutt and S. tristani Denis. Salina was previously known to occur in three Brazilian states, and this is now updated to include 19 states with 12 recorded species. A new proposal of morphological character description and illustration, and an identification key for the celebensis group are provided. A hypothesis for the phylogenetic relationships among 34 species of Salina (about 50% of the 72 described species) allowed three main pursuits: (a) a reevaluation of Salina species groups; (b) the first explicit interpretation of how morphological characters of these springtails may have changed during the course of the diversification of the taxon; and (c) an evaluation of the historical biogeographic connections of Salina, with an emphasis on the celebensis group distribution to the New World.

scholarly journals The intensity of slope and fluvial processes after a catastrophic windthrow event in small catchments in the Tatra Mountains

2021 ◽  
Vol 18 (6) ◽  
pp. 1405-1423
Author(s):  
Dariusz Strzyżowski ◽  
Elżbieta Gorczyca ◽  
Kazimierz Krzemień ◽  
Mirosław Żelazny
Keyword(s):  
Environmental Changes ◽  
Bedload Transport ◽  
Strong Wind ◽  
Tatra Mountains ◽  
Salvage Logging ◽  
Fluvial Processes ◽  
Wind Events ◽  
And Control ◽  
The Tatra Mountains ◽  
The Impact

AbstractStrong wind events frequently result in creating large areas of windthrow, which causes abrupt environmental changes. Bare soil surfaces within pits and root plates potentially expose soil to erosion. Absence of forest may alter the dynamics of water circulation. In this study we attempt to answer the question of whether extensive windthrows influence the magnitude of geomorphic processes in 6 small second- to third-order catchments with area ranging from 0.09 km2 to 0.8 km2. Three of the catchments were significantly affected by a windthrow which occurred in December 2013 in the Polish part of the Tatra Mountains, and the other three catchments were mostly forested and served as control catchments. We mapped the pits created by the windthrow and the linear scars created by salvage logging operations in search of any signs of erosion within them. We also mapped all post-windthrow landslides created in the windthrow-affected catchments. The impact of the windthrow on the fluvial system was investigated by measuring a set of channel characteristics and determining bedload transport intensity using painted tracers in all the windthrow-affected and control catchments. Both pits and linear scars created by harvesting tend to become overgrown by vegetation in the first several years after the windthrow. The only signs of erosion were observed in 10% of the pits located on convergent slopes. During the period from the windthrow event in 2013 until 2019, 5 very small (total area <100 m2) shallow landslides were created. The mean distance of bedload transport was similar (t-test, p=0.05) in most of the windthrow-affected and control catchments. The mapping of channels revealed many cases of root plates fallen into a channel and pits created near a channel. A significant amount of woody debris delivered into the channels influenced the activity of fluvial processes by creating alternating zones of erosion and accumulation.

Species distribution modeling reveals the ecological niche of extinct megafauna from South America

2021 ◽  
pp. 1-8
Author(s):  
Thaísa Araújo ◽  
Helena Machado ◽  
Dimila Mothé ◽  
Leonardo dos Santos Avilla
Keyword(s):  
South America ◽  
Species Distribution ◽  
Environmental Changes ◽  
Species Distribution Modeling ◽  
Human Action ◽  
Northeastern Brazil ◽  
Climate Conditions ◽  
Middle Holocene ◽  
Distribution Modeling ◽  
The Impact

Abstract Climatic and environmental changes, as well as human action, have been cited as potential causes for the extinction of megafauna in South America at the end of the Pleistocene. Among megamammals lineages with Holarctic origin, only horses and proboscideans went extinct in South America during this period. This study aims to understand how the spatial extent of habitats suitable for Equus neogeus and Notiomastodon platensis changed between the last glacial maximum (LGM) and the middle Holocene in order to determine the impact that climatic and environmental changes had on these taxa. We used species distribution modeling to estimate their potential extent on the continent and found that both species occupied arid and semiarid open lands during the LGM, mainly in the Pampean region of Argentina, southern and northeastern Brazil, and parts of the Andes. However, when climate conditions changed from dry and cold during the LGM to humid and warm during the middle Holocene, the areas suitable for these taxa were reduced dramatically. These results support the hypothesis that climatic changes were a driving cause of extinction of these megamammals in South America, although we cannot rule out the impact of human actions or other potential causes for their extinction.

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