land bridge
Recently Published Documents


TOTAL DOCUMENTS

352
(FIVE YEARS 81)

H-INDEX

43
(FIVE YEARS 4)

2022 ◽  
pp. 1-20
Author(s):  
İsmail Baykara ◽  
M. Akif Sarıkaya ◽  
Serkan Şahin ◽  
Berkay Dinçer ◽  
Esin Ünal

The province of Van in north-eastern Turkey served as a land bridge between Africa and Eurasia during the Palaeolithic. The region is of particular relevance for understanding the movement of hominins between these continents. This study concerns the lithic remains from a locality at Gürgürbaba Hill, named Locality 010, north of the village of Ulupamir (Erciş district). Locality 010 was dated to 311±32 kya by terrestrial cosmogenic nuclides method, which coincides with Marine Isotope Stage 9 (MIS 9), a Middle Pleistocene interglacial period. The assemblage from this site is attributed to the Late Acheulean and resembles that of the southern Caucasus. This similarity indicates that the artefacts from Locality 010 were probably produced by late Lower Palaeolithic technology in a broad sense. These findings suggest local adaptations of late Middle Pleistocene hominins to high plateau environments.


2022 ◽  
Vol 9 ◽  
Author(s):  
Matti A. Niissalo ◽  
Elliot M. Gardner ◽  
Gillian S. Khew ◽  
Otakar Šída ◽  
Axel Dalberg Poulsen ◽  
...  

Lowiaceae (order Zingiberales) is a small family of forest herbs in Southeast Asia. All species belong to the genus Orchidantha. They are known for possessing orchid-like flowers that are smelly, apparently mimicking dead animals, feces, or mushrooms. Little is known of the biogeographic patterns or character evolution of the family. We sampled the family extensively, including many recently discovered species, and reconstructed the phylogeny of the family using HybSeq with Lowiaceae-specific RNA baits. Our phylogenetic reconstructions confirm that the family is most closely related to Strelitziaceae, and that species with dark, foul-smelling flowers form a grade in which a clade of species with paler flowers are embedded. The pale-flowered species produce a distinct odor, resembling edible mushrooms. Apart from a single species, the species from Borneo form a clade, and the same is true for Indochinese species. The remaining species form a more widespread clade. A biogeographic analysis shows that the distribution of Lowiaceae can explained by vicariance and gradual dispersal from a shared ancestral range of Borneo and Indochina. There is no evidence of long-distance dispersal, only a later extension in distribution to Peninsular Malaysia which coincides with the presence of a land bridge. Different directions of spread are possible, but none require long-distance dispersal. The results are consistent with the geological history of Southeast Asia. In particular, the relatively early isolation between Indochina and Borneo could be explained by the presence of a sea barrier that developed 10–15 MYA, and the continuous movement of plant species between Borneo and Peninsular Malaysia could be explained by a land bridge that existed until c. 5 MYA. The lack of an extensive land bridge with a suitable habitat may explain the absence of this genus from Sumatra and other Indonesian islands aside from Borneo. The strict reliance on a continuous habitat for the range expansion of Lowiaceae can be explained by their fruits and seeds, which lack obvious adaptations for long-distance dispersal. The inability to disperse to new areas may also explain why the extant species have very restricted distributions.


2021 ◽  
Vol 7 (12) ◽  
pp. 1088
Author(s):  
Junmin Liang ◽  
Lorenzo Pecoraro ◽  
Lei Cai ◽  
Zhilin Yuan ◽  
Peng Zhao ◽  
...  

Armillaria species have a global distribution and play various roles in the natural ecosystems, e.g., pathogens, decomposers, and mycorrhizal associates. However, their taxonomic boundaries, speciation processes, and origin are poorly understood. Here, we used a phylogenetic approach with 358 samplings from Europe, East Asia, and North America to delimit the species boundaries and to discern the evolutionary forces underpinning divergence and evolution. Three species delimitation methods indicated multiple unrecognized phylogenetic species, and biological species recognition did not reflect the natural evolutionary relationships within Armillaria; for instance, biological species of A. mellea and D. tabescens are divergent and cryptic species/lineages exist associated with their geographic distributions in Europe, North America, and East Asia. While the species-rich and divergent Gallica superclade might represent three phylogenetic species (PS I, PS II, and A. nabsnona) that undergo speciation. The PS II contained four lineages with cryptic diversity associated with the geographic distribution. The genus Armillaria likely originated from East Asia around 21.8 Mya in early Miocene when Boreotropical flora (56–33.9 Mya) and the Bering land bridge might have facilitated transcontinental dispersal of Armillaria species. The Gallica superclade arose at 9.1 Mya and the concurrent vicariance events of Bering Strait opening and the uplift of the northern Tibetan plateau might be important factors in driving the lineage divergence.


2021 ◽  
Author(s):  
Yong Chee Keita Sin ◽  
Nadiah P. Kristensen ◽  
Chyi Yin Gwee ◽  
Ryan A. Chisholm ◽  
Frank E. Rheindt

Biology ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1282
Author(s):  
Artem N. Bondaryuk ◽  
Tatiana E. Peretolchina ◽  
Elena V. Romanova ◽  
Anzhelika V. Yudinceva ◽  
Evgeny I. Andaev ◽  
...  

In this paper, we revealed the genetic structure and migration history of the Powassan virus (POWV) reconstructed based on 25 complete genomes available in NCBI and ViPR databases (accessed in June 2021). The usage of this data set allowed us to perform a more precise assessment of the evolutionary rate of this virus. In addition, we proposed a simple Bayesian technique for the evaluation and visualization of ‘temporal signal dynamics’ along the phylogenetic tree. We showed that the evolutionary rate value of POWV is 3.3 × 10−5 nucleotide substitution per site per year (95% HPD, 2.0 × 10−5–4.7 × 10−5), which is lower than values reported in the previous studies. Divergence of the most recent common ancestor (MRCA) of POWV into two independent genetic lineages most likely occurred in the period between 2600 and 6030 years ago. We assume that the divergence of the virus lineages happened due to the melting of glaciers about 12,000 years ago, which led to the disappearance of the Bering Land Bridge between Eurasia and North America (the modern Alaskan territory) and spatial division of the viral areal into two parts. Genomic data provide evidence of the virus migrations between two continents. The mean migration rate detected from the Far East of Russia to North America was one event per 1750 years. The migration to the opposite direction occurred approximately once per 475 years.


Author(s):  
María E Montoya

Abstract In both scholarly work and popular imagination, the American West is the final destination of migrant from Europe and Mexico. The stories of those migrants, however, obscure the first migration (12,000 BP) from Asia into North America. That migration across the now-submerged land bridge of Beringia ended humanity’s millennia-long journey across the globe that originated in Africa more than 50,000 years earlier. Using two examples, this essay reflects on how the Asian origins of the first Americans have been transformed into myths that conceal humanity’s migratory nature. First, in Chinese Communist propaganda, those origins are transformed into the myth of Peking Man as a branch of humanity originating in China rather than Africa. Second, in the writing of Rudolfo Anaya, those Asian origins are transformed into the myth of homogenous “Brown Brothers” united against white imperialists. Rather than rely on a myth of racial unity in some original homeland, this essay urges reliance on the shared experience of migration and home-making in hostile environments as the true source of our common humanity. Anaya’s Golden Carp, symbol of the life-giving fierce of water in an arid environment, captures this common human predicament stretching from Tibet and Xinjiang to New Mexico, epitomizing the American West as the place where humanity has been reunited, the home to the last wanderers of the human race.


2021 ◽  
Author(s):  
Menglin Wang ◽  
Simon Hellemans ◽  
Jan Šobotník ◽  
Jigyasa Arora ◽  
Aleš Buček ◽  
...  

AbstractTermites are social cockroaches distributed throughout warm temperate and tropical ecosystems. The ancestor of modern termites (crown-Isoptera) occurred during the earliest Cretaceous, approximately 140 million years ago, suggesting that both vicariance through continental drift and overseas dispersal may have shaped the distribution of early diverging termite lineages. We reconstruct the historical biogeography of three early diverging termite families – Stolotermitidae, Hodotermitidae, and Archotermopsidae – using the nuclear rRNA genes and mitochondrial genomes of 27 samples. Our analyses confirmed the monophyly of Stolotermitidae + Hodotermitidae + Archotermopsidae (clade Teletisoptera), with Stolotermitidae diverging from a monophyletic Hodotermitidae + Archotermopsidae approximately 100.3 Ma (94.3–110.4 Ma, 95% HPD), and with Archotermopsidae paraphyletic to a monophyletic Hodotermitidae. The Oriental Archotermopsis and the Nearctic Zootermopsis diverged 50.8 Ma (40.7–61.4 Ma, 95% HPD) before land connections between the Palearctic region and North America ceased to exist. The African Hodotermes + Microhodotermes diverged from Anacanthotermes, a genus found in Africa and Asia, 32.1 Ma (24.8–39.9 Ma, 95% HPD), and the most recent common ancestor of Anacanthotermes lived 10.7 Ma (7.3–14.3 Ma, 95% HPD), suggesting that Anacanthotermes dispersed to Asia using the land bridge connecting Africa and Eurasia ∼18–20 Ma. In contrast, the common ancestors of modern Porotermes and Stolotermes lived 20.2 Ma (15.7–25.1 Ma, 95% HPD) and 26.6 Ma (18.3–35.6 Ma, 95% HPD), respectively, indicating that the presence of these genera in South America, Africa, and Australia involved over-water dispersals. Our results suggest that early diverging termite lineages acquired their current distribution through a combination of over-water dispersals and dispersal via land bridges. We clarify the classification by resolving the paraphyly of Archotermopsidae, restricting the family to Archotermopsis and Zootermopsis, and elevating Hodotermopsinae (Hodotermopsis) as Hodotermopsidae (status novum).


Diversity ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 622
Author(s):  
Klemen Čandek ◽  
Ingi Agnarsson ◽  
Greta J. Binford ◽  
Matjaž Kuntner

Dispersal ability can affect levels of gene flow thereby shaping species distributions and richness patterns. The intermediate dispersal model of biogeography (IDM) predicts that in island systems, species diversity of those lineages with an intermediate dispersal potential is the highest. Here, we tested this prediction on long-jawed spiders (Tetragnatha) of the Caribbean archipelago using phylogenies from a total of 318 individuals delineated into 54 putative species. Our results support a Tetragnatha monophyly (within our sampling) but reject the monophyly of the Caribbean lineages, where we found low endemism yet high diversity. The reconstructed biogeographic history detects a potential early overwater colonization of the Caribbean, refuting an ancient vicariant origin of the Caribbean Tetragnatha as well as the GAARlandia land-bridge scenario. Instead, the results imply multiple colonization events to and from the Caribbean from the mid-Eocene to late-Miocene. Among arachnids, Tetragnatha uniquely comprises both excellently and poorly dispersing species. A direct test of the IDM would require consideration of three categories of dispersers; however, long-jawed spiders do not fit one of these three a priori definitions, but rather represent a more complex combination of attributes. A taxon such as Tetragnatha, one that readily undergoes evolutionary changes in dispersal propensity, can be referred to as a ‘dynamic disperser’.


2021 ◽  
Vol 58 ◽  
pp. 24-32
Author(s):  
Friedhelm Krupp

Im oberen Miozän kollidierte die afroarabische Platte mit Eurasien. So entstand die Gomphotherium- Landbrücke, welche Paläarktis, Orientalis und Afrotropis miteinander verband und einen Faunenaustausch zwischen diesen Regionen über ständig wechselnde Gewässernetze ermöglichte, der jedoch mit zunehmender Aridität immer mehr eingeschränkt wurde. In den 1970er Jahren initiierte Ragnar Kinzelbach mit einer Serie von Forschungsreisen die systematische Erforschung der Hydrofauna der Levante, die er und seine Schüler*innen später auf den gesamten Vorderen Orient ausweiteten. Die umfangreichen, in Museen deponierten Sammlungen, die aufgrund fortschreitender Umweltzerstörung und bewaffneter Konflikte in der Region heute nur eingeschränkt zusammengetragen werden können, bilden eine wichtige Grundlage für fortlaufende Forschungsarbeiten und Naturschutzinitiativen. Anhand einiger Beispiele werden die rezente Biodiversität der Binnengewässer der Region und die Geschichte ihrer Besiedlung mit Süßwasserorganismen umrissen. Research into the Critically Endangered Freshwater Fauna of the Middle East Abstract: During the Upper Miocene, the Afro-Arabian Plate collided with Eurasia, giving rise to the Gomphotherium land bridge, which connects the Palaearctic, Oriental and Afrotropical realms, allowing for an exchange of faunal elements among these realms via an ever-changing network of freshwater connections. This migration, however, was soon restricted by increasing aridity. In the 1970s, Ragnar Kinzelbach initiated research activities on the freshwater fauna of the Levant, which he and his students later on extended to the entire Middle East. Extensive collections were deposited in museums, serving scientific research and conservation initiatives. Given increasing degradation of freshwater ecosystems and armed conflicts in the region, most of these collecting activities would no longer be possible today. The extant biodiversity of the region’s inland waters and its historical biogeography are briefly outlined.


2021 ◽  
Author(s):  
Alexander T Salis ◽  
Sarah C E Bray ◽  
Michael S Y Lee ◽  
Holly Heiniger ◽  
Ross Barnett ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document