scholarly journals Cenozoic aridization in Central Eurasia shaped diversification of toad-headed agamas (Phrynocephalus; Agamidae, Reptilia)

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4543 ◽  
Author(s):  
Evgeniya N. Solovyeva ◽  
Vladimir S. Lebedev ◽  
Evgeniy A. Dunayev ◽  
Roman A. Nazarov ◽  
Anna A. Bannikova ◽  
...  
Keyword(s):  
Body Size ◽  
Environmental Changes ◽  
Climatic Factors ◽  
Phylogenetic Analyses ◽  
Late Oligocene ◽  
Central Eurasia ◽  
Biogeographic History ◽  
Middle Asia ◽  
History Of ◽  
The Impact

We hypothesize the phylogenetic relationships of the agamid genusPhrynocephalusto assess how past environmental changes shaped the evolutionary and biogeographic history of these lizards and especially the impact of paleogeography and climatic factors.Phrynocephalusis one of the most diverse and taxonomically confusing lizard genera. As a key element of Palearctic deserts, it serves as a promising model for studies of historical biogeography and formation of arid habitats in Eurasia. We used 51 samples representing 33 of 40 recognized species ofPhrynocephaluscovering all major areas of the genus. Molecular data included four mtDNA (COI,ND2,ND4,Cytb; 2,703 bp) and four nuDNA protein-coding genes (RAG1,BDNF,AKAP9,NKTR; 4,188 bp). AU-tests were implemented to test for significant differences between mtDNA- and nuDNA-based topologies. A time-calibrated phylogeny was estimated using a Bayesian relaxed molecular clock with nine fossil calibrations. We reconstructed the ancestral area of origin, biogeographic scenarios, body size, and the evolution of habitat preference. Phylogenetic analyses of nuDNA genes recovered a well-resolved and supported topology. Analyses detected significant discordance with the less-supported mtDNA genealogy. The position ofPhrynocephalus mystaceusconflicted greatly between the two datasets. MtDNA introgression due to ancient hybridization best explained this result. MonophyleticPhrynocephaluscontained three main clades: (I) oviparous species from south-western and Middle Asia; (II) viviparous species of Qinghai–Tibetan Plateau (QTP); and (III) oviparous species of the Caspian Basin, Middle and Central Asia.Phrynocephalusoriginated in late Oligocene (26.9 Ma) and modern species diversified during the middle Miocene (14.8–13.5 Ma). The reconstruction of ancestral areas indicated thatPhrynocephalusoriginated in Middle East–southern Middle Asia. Body size miniaturization likely occurred early in the history ofPhrynocephalus. The common ancestor ofPhrynocephalusprobably preferred sandy substrates with the inclusion of clay or gravel. The time of Agaminae radiation and origin ofPhrynocephalusin the late Oligocene significantly precedes the landbridge between Afro-Arabia and Eurasia in the Early Miocene. Diversification ofPhrynocephaluscoincides well with the mid-Miocene climatic transition when a rapid cooling of climate drove progressing aridification and the Paratethys salinity crisis. These factors likely triggered the spreading of desert habitats in Central Eurasia, whichPhrynocephalusoccupied. The origin of the viviparous Tibetan clade has been associated traditionally with uplifting of the QTP; however, further studies are needed to confirm this. Progressing late Miocene aridification, the decrease of the Paratethys Basin, orogenesis, and Plio–Pleistocene climate oscillations likely promoted further diversification withinPhrynocephalus. We discussPhrynocephalustaxonomy in scope of the new analyses.

scholarly journals The role of Central American barriers in shaping the evolutionary history of the northernmost glassfrog,Hyalinobatrachium fleischmanni(Anura: Centrolenidae)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6115 ◽  
Author(s):  
Angela M. Mendoza ◽  
Wilmar Bolívar-García ◽  
Ella Vázquez-Domínguez ◽  
Roberto Ibáñez ◽  
Gabriela Parra Olea
Keyword(s):  
Genetic Structure ◽  
Central America ◽  
Population Expansion ◽  
Central American ◽  
Fault System ◽  
Mountain Range ◽  
Amphibian Species ◽  
Biogeographic History ◽  
History Of ◽  
The Impact

The complex geological history of Central America has been useful for understanding the processes influencing the distribution and diversity of multiple groups of organisms. Anurans are an excellent choice for such studies because they typically exhibit site fidelity and reduced movement. The objective of this work was to identify the impact of recognized geographic barriers on the genetic structure, phylogeographic patterns and divergence times of a wide-ranging amphibian species,Hyalinobatrachium fleischmanni. We amplified three mitochondrial regions, two coding (COI and ND1) and one ribosomal (16S), in samples collected from the coasts of Veracruz and Guerrero in Mexico to the humid forests of Chocó in Ecuador. We examined the biogeographic history of the species through spatial clustering analyses (Geneland and sPCA), Bayesian and maximum likelihood reconstructions, and spatiotemporal diffusion analysis. Our data suggest a Central American origin ofH. fleischmanniand two posterior independent dispersals towards North and South American regions. The first clade comprises individuals from Colombia, Ecuador, Panama and the sister speciesHyalinobatrachium tatayoi; this clade shows little structure, despite the presence of the Andes mountain range and the long distances between sampling sites. The second clade consists of individuals from Costa Rica, Nicaragua, and eastern Honduras with no apparent structure. The third clade includes individuals from western Honduras, Guatemala, and Mexico and displays deep population structure. Herein, we synthesize the impact of known geographic areas that act as barriers to glassfrog dispersal and demonstrated their effect of differentiatingH. fleischmanniinto three markedly isolated clades. The observed genetic structure is associated with an initial dispersal event from Central America followed by vicariance that likely occurred during the Pliocene. The southern samples are characterized by a very recent population expansion, likely related to sea-level and climatic oscillations during the Pleistocene, whereas the structure of the northern clade has probably been driven by dispersal through the Isthmus of Tehuantepec and isolation by the Motagua–Polochic–Jocotán fault system and the Mexican highlands.

Using Diatoms as Ecological and Paleoecological Indicators in Riverine Environments

2007 ◽  
Vol 13 ◽  
pp. 121-130
Author(s):  
Jeffery R. Stone
Keyword(s):  
Spatial Distribution ◽  
Environmental Changes ◽  
Climatic Factors ◽  
Diatom Assemblages ◽  
Meandering River ◽  
Rates Of Change ◽  
Terminal Lakes ◽  
Riverine Systems ◽  
The Impact ◽  
Selection Of

Fossil diatom assemblages are useful for reconstructing past environmental changes in riverine systems. However, few studies have attempted to utilize paleolimnological techniques in these settings. Analysis of sediments from riverine environments can provide key information predating the impact of human development, which cannot be acquired by other means. Paleolimnological techniques can be used to determine the natural variability in these systems and to estimate the magnitude and rates of change that the environment may have undergone as a result of anthropogenic or climatic factors, and to provide realistic goals for management of negatively-impacted systems.Reconstructing past riverine settings requires an understanding of the factors that control the spatial distribution of diatoms in riverine settings; this paper discusses the impact of resources, stressors, and disturbance events, which are the primary controls on the distribution of benthic diatoms in modern riverine environments. A selection of case studies that utilize paleolimnological techniques to infer past stream hydrology are also discussed; these examples encompass the use of fossil diatom assemblages from sediments recovered from lowland floodplain and meandering river systems, estuarine environments, fluvial lakes, arctic deltaic environments, and terminal lakes.

scholarly journals Outline of the development of research on the impact of Neolithic settlements on the transformation on loess landscapes in southern Poland

2020 ◽  
Vol 8 (2) ◽  
pp. 32-44 ◽  
Author(s):  
Kamila Ryzner ◽  
Piotr Owczarek
Keyword(s):  
Environmental Changes ◽  
Anthropogenic Factors ◽  
Functional Responses ◽  
Natural Systems ◽  
River Terraces ◽  
Current State ◽  
History Of ◽  
Response To Water ◽  
Landscape Transformations ◽  
The Impact

AbstractDuring the last few decades, many case studies have focused on landscape transformations in response to water erosion, human impact, and climate changes. This article presents a review and comparison of the current state of knowledge on conducted research on the impact of the activities of early humans on the relief and forms of loess areas in Poland based on the results of a variety of dating methods (OSL, TL, C14, 137Cs, palynology, dendrochronology etc.). The influence of land-use activity since the first permanent settlements (8,000–5,200 BP) played a major role in the development of certain sand sediment terrain forms: gullies, river terraces, the filling of isolated depressions and alluvial fans in the loess areas. As a result, a simplified scheme of landscape evolution was created along with a map of the most investigated areas by authors. The main problem was to differentiate the influence of anthropogenic factors from natural ones occurring either simultaneously or alternatively. The developed deposits form a geo-archive which has recorded the history of environmental changes. A detailed analysis of the sedimentary structures provides the possibility to reconstruct and understand past functional responses in natural systems. It is important to consider the impact of climate change and human influence over the course of history on a specific geomorphological system. This can help to predict future land changes and likely hazards.

scholarly journals A revised global biogeography of turtles

2015 ◽  
Author(s):  
Walter G. Joyce ◽  
Márton Rabi
Keyword(s):  
Middle Jurassic ◽  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Sensu Stricto ◽  
Early History ◽  
Marine Turtles ◽  
Biogeographic History ◽  
Global Presence ◽  
History Of ◽  
Phylogenetic Hypotheses

Background. Over the course of the last decades, much effort has gone into unraveling the biogeographic history of turtles, but while much progress has been achieved in resolving post- Jurassic dispersal events, traditional phylogenetic hypotheses have yielded incongruous results in regards to the early history of the group. Methods. We re-evaluate the fossil record of turtles in context of recent phylogenetic analyses and fossil finds, including the extensive record of fragmentary but diagnostic remains. Given that near-coastal and marine turtles readily disperse across aquatic barriers, a broad set of neritic to pelagic groups were disregarded from consideration. Significant disagreement still exists among current phylogenetic hypotheses and we therefore place much effort into tracing the fossil record of unambiguously monophyletic groups. We finally employed molecular backbone constraints, given that the molecular phylogenies are more consistent with the fossil record than current, morphological phylogenies. Results. Among derived, aquatic turtles, we recognize four clades that can be traced back to discrete biogeographic centers: Paracryptodira in North America and Europe, Pan- Cryptodira in Asia, Pan-Pelomedusoides in northern Gondwanan landmasses and Pan- Chelidae in southern Gondwanan landmasses. This pattern is partially mirrored by three clades of primarily terrestrial, basal turtles: Solemydidae in North American and Europe, Sichuanchelyidae in Asia, and Meiolaniformes sensu stricto in southern Gondwanan landmasses. Although the exact interrelationships of these clades remain unclear, most can be traced back to the Middle Jurassic. Discussion. The conclusion that the two primary lineages of pleurodires and paracryptodires can be traced back to mutually exclusive land masses is not novel, but the realization that the early history of pan-cryptodires is restricted to Asia has not been realized previously, because traditional phylogenies implied an early, global presence of pan-cryptodires. The timing of the origin of the three primary clades of derived turtles (i.e., Pan-Pleurodira, Pan-Cryptodira, and Paracryptodira) correlates with the opening of the central Atlantic and the formation of the Turgai Strait in the Middle Jurassic, somewhat later than predicted by molecular calibration studies. The primary diversity of extant turtles therefore appears to have been driven by vicariance. A similar hypothesis could also be formulated for the three clades of basal turtles that survive at least into the Late Cretaceous, but given that their combined monophyly remains uncertain, it is unclear if their diversity was also driven by vicariance, or if they emulate a vicariance-like pattern. Although most groups remained within their primary geographic range throughout their evolutionary history, the dominant vicariance signal was thoroughly obfuscated by rich dispersal from littoral to marine turtles and crown cryptodires.

scholarly journals Tracking of Anopheles stephensi in Ethiopia using mitochondrial DNA reveals pattern of spread

2021 ◽  
Author(s):  
Tamar E Carter ◽  
Solomon Yared ◽  
Dejene Getachew ◽  
Joseph Spear ◽  
Sae Hee Choi ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
South Asian ◽  
Anopheles Stephensi ◽  
Phylogenetic Analyses ◽  
Eastern Ethiopia ◽  
Multiple Introductions ◽  
Minimum Spanning Network ◽  
History Of ◽  
Spread Analysis ◽  
The Impact

The recent detection of the South Asian malaria vector Anopheles stephensi in the Horn of Africa (HOA) raises concerns about the impact of this mosquito on malaria transmission in the region. The mode and history of introduction is important for predicting the likelihood of continued introduction and future spread. Analysis of An. stephensi genetic diversity and population structure can provide insight into the history of the mosquito in the HOA. We investigated genetic diversity of An. stephensi in eastern Ethiopia where detection suggests a range expansion to this region to understand the history of this invasive population. We sequenced the cytochrome oxidase subunit I (COI) and cytochrome B gene (CytB) in 187 An. stephensi collected from 10 sites in Ethiopia in 2018. Phylogenetic analyses using a maximum-likelihood approach and minimum spanning network were conducted for Ethiopian sequences. Molecular identification of bloodmeal sources was also performed using universal vertebrate CytB sequencing. Six COI-CytB haplotypes were observed based on five segregating sites, with the highest number of haplotypes in the northeastern sites (Semera, Bati, and Gewana towns) relative to the southeastern sites (Kebridehar, Godey, and Degehabur) in eastern Ethiopia. In the phylogenetic and network analysis, we observed population differentiation based on the distribution of the haplotypes across the northeastern and central sites (Erer Gota, Dire Dawa, and Awash Sebat Kilo) compared to the southeastern sites and evidence of a South Asian origin of the HOA An. stephensi lineages. The presence of the putative South Asian haplotype of origin at sites closest to Ethiopia's northeastern borders support route of introductions into Ethiopia from the northeast. Finally, molecular bloodmeal analysis revealed evidence of feeding on bovines, goats, dogs, and humans, as well as evidence of multiple (mixed) blood meals. In conclusion, we find support for the hypothesis for the recent expansion of An. stephensi into southeastern Ethiopia with multiple introductions. We also find evidence that supports the hypothesis that HOA An. stephensi populations originate from South Asia rather than the Arabian Peninsula. The evidence of both zoophagic and anthropophagic feeding support the potential for livestock movement to play a role in vector spread in this region.

scholarly journals Hyainailourine and teratodontine cranial material from the late Eocene of Egypt and the application of parsimony and Bayesian methods to the phylogeny and biogeography of Hyaenodonta (Placentalia, Mammalia)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2639 ◽  
Author(s):  
Matthew R. Borths ◽  
Patricia A. Holroyd ◽  
Erik R. Seiffert
Keyword(s):  
North America ◽  
Bayesian Methods ◽  
Middle Eocene ◽  
Phylogenetic Analyses ◽  
Late Eocene ◽  
Biogeographic History ◽  
Close Relationship ◽  
History Of ◽  
New Material ◽  
Latest Eocene

Hyaenodonta is a diverse, extinct group of carnivorous mammals that included weasel- to rhinoceros-sized species. The oldest-known hyaenodont fossils are from the middle Paleocene of North Africa and the antiquity of the group in Afro-Arabia led to the hypothesis that it originated there and dispersed to Asia, Europe, and North America. Here we describe two new hyaenodont species based on the oldest hyaenodont cranial specimens known from Afro-Arabia. The material was collected from the latest Eocene Locality 41 (L-41, ∼34 Ma) in the Fayum Depression, Egypt.Akhnatenavus nefertiticyonsp. nov. has specialized, hypercarnivorous molars and an elongate cranial vault. InA. nefertiticyonthe tallest, piercing cusp on M1–M2is the paracone.Brychotherium ephalmosgen. et sp. nov. has more generalized molars that retain the metacone and complex talonids. InB. ephalmosthe tallest, piercing cusp on M1–M2is the metacone. We incorporate this new material into a series of phylogenetic analyses using a character-taxon matrix that includes novel dental, cranial, and postcranial characters, and samples extensively from the global record of the group. The phylogenetic analysis includes the first application of Bayesian methods to hyaenodont relationships.B. ephalmosis consistently placed within Teratodontinae, an Afro-Arabian clade with several generalist and hypercarnivorous forms, andAkhnatenavusis consistently recovered in Hyainailourinae as part of an Afro-Arabian radiation. The phylogenetic results suggest that hypercarnivory evolved independently three times within Hyaenodonta: in Teratodontinae, in Hyainailourinae, and in Hyaenodontinae. Teratodontines are consistently placed in a close relationship with Hyainailouridae (Hyainailourinae + Apterodontinae) to the exclusion of “proviverrines,” hyaenodontines, and several North American clades, and we propose that the superfamily Hyainailouroidea be used to describe this relationship. Using the topologies recovered from each phylogenetic method, we reconstructed the biogeographic history of Hyaenodonta using parsimony optimization (PO), likelihood optimization (LO), and Bayesian Binary Markov chain Monte Carlo (MCMC) to examine support for the Afro-Arabian origin of Hyaenodonta. Across all analyses, we found that Hyaenodonta most likely originated in Europe, rather than Afro-Arabia. The clade is estimated by tip-dating analysis to have undergone a rapid radiation in the Late Cretaceous and Paleocene; a radiation currently not documented by fossil evidence. During the Paleocene, lineages are reconstructed as dispersing to Asia, Afro-Arabia, and North America. The place of origin of Hyainailouroidea is likely Afro-Arabia according to the Bayesian topologies but it is ambiguous using parsimony. All topologies support the constituent clades–Hyainailourinae, Apterodontinae, and Teratodontinae–as Afro-Arabian and tip-dating estimates that each clade is established in Afro-Arabia by the middle Eocene.

scholarly journals Out of Himalaya: the impact of past Asian environmental changes on the evolutionary and biogeographical history of Dipodoidea (Rodentia)

2015 ◽  
Vol 42 (5) ◽  
pp. 856-870 ◽  
Author(s):  
Julie Pisano ◽  
Fabien L. Condamine ◽  
Vladimir Lebedev ◽  
Anna Bannikova ◽  
Jean-Pierre Quéré ◽  
...  
Keyword(s):  
Environmental Changes ◽  
History Of ◽  
The Impact

scholarly journals Phylogenomics reveals a complex evolutionary history of lobed-leaf white oaks in western North America

Genome ◽  
2017 ◽  
Vol 60 (9) ◽  
pp. 733-742 ◽  
Author(s):  
John D. McVay ◽  
Duncan Hauser ◽  
Andrew L. Hipp ◽  
Paul S. Manos
Keyword(s):  
Phylogenetic Analyses ◽  
Introgressive Hybridization ◽  
Sympatric Species ◽  
Robust Estimate ◽  
History Of ◽  
Tree Space ◽  
Quercus Gambelii ◽  
Lobed Leaf ◽  
The Impact ◽  
Historical Range

Species within the genus Quercus (oak) hybridize in complex patterns that have yet to be fully explored with phylogenomic data. Analyses to date have recovered reasonable divergent patterns, suggesting that the impact of introgression may not always be obvious in inferred oak phylogenies. We explore this phenomenon using RADseq data for 136 samples representing 54 oak species by conducting phylogenetic analyses designed to distinguish signals of lineage diversification and hybridization, focusing on the lobed-leaf species Quercus gambelii, Q. lobata, and Q. garryana in the context of a broad sampling of allied white oaks (Quercus section Quercus), and particularly the midwestern Q. macrocarpa. We demonstrate that historical introgressive hybridization between once sympatric species affects phylogeny estimation. Historical range expansion during periods of favorable climate likely explains our observations; analyses support genetic exchange between ancestral populations of Q. gambelii and Q. macrocarpa. We conclude that the genomic consequences of introgression caused the attraction of distant lineages in phylogenetic tree space, and that introgressive and divergent signals can be disentangled to produce a robust estimate of the phylogenetic history of the species.

scholarly journals Did true frogs ‘dispersify’?

2017 ◽  
Vol 13 (8) ◽  
pp. 20170299 ◽  
Author(s):  
Kin Onn Chan ◽  
Rafe M. Brown
Keyword(s):  
Range Expansion ◽  
Large Scale ◽  
Late Eocene ◽  
Fundamental Interest ◽  
Biogeographic History ◽  
Ideal System ◽  
History Of ◽  
Biogeographic Regions ◽  
Geographical Expansion ◽  
The Impact

The interplay between range expansion and concomitant diversification is of fundamental interest to evolutionary biologists, particularly when linked to intercontinental dispersal and/or large scale extinctions. The evolutionary history of true frogs has been characterized by circumglobal range expansion. As a lineage that survived the Eocene–Oligocene extinction event (EOEE), the group provides an ideal system to test the prediction that range expansion triggers increased net diversification. We constructed the most densely sampled, time-calibrated phylogeny to date in order to: (i) characterize tempo and patterns of diversification; (ii) assess the impact of the EOEE; and (iii) test the hypothesis that range expansion was followed by increased net diversification. We show that late Eocene colonization of novel biogeographic regions was not affected by the EOEE and surprisingly, global expansion was not followed by increased net diversification. On the contrary, the diversification rate declined or did not shift following geographical expansion. Thus, the diversification history of true frogs contradicts the prevailing expectation that amphibian net diversification accelerated towards the present or increased following range expansion. Rather, our results demonstrate that despite their dynamic biogeographic history, true frogs diversified at a relatively constantly rate, even as they colonized the major land masses of Earth.

scholarly journals Sustainability and Livelihoods

2021 ◽  
Author(s):  
Chinta Srinivas
Keyword(s):  
Environmental Sustainability ◽  
Habitat Management ◽  
Environmental Changes ◽  
Developing Economies ◽  
Agricultural Practices ◽  
Economic Activities ◽  
History Of ◽  
The Impact ◽  
Environmental Landscape

The word environmental sustainability of late has been used as catch word for illustrating the climate change and subsequent sequential impact of various aspects of environmental landscape that include soil management, gaseous exchange, nutrient cycling, carbon emission, rainfall etc., Interpretation of environmental changes are interpreted based on very few trends which need not necessarily cause short term or long term impacts. The impact assessment of a region fundamentally depends on region specific history of habitat management, human interference, agricultural practices, Economic livelihood activities which depend on available natural resources and seasonality of intensity of activities. In the present study efforts are made to indentify the major NTFP based livelihood economic activities and relate the habitat management aspects along with commercial invasion that became detrimental to environmental threshold to call for sustainability alarm. The livelihoods in various developing economies have different environmental impacts. Such assessment of economic activities have any real environmentally detrimental consequences or is it being essentially over emphasizing to create such fears have been analyzed.

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