scholarly journals Unraveling the evolutionary history of the cave-dwelling Dysderidae in the Dinarides

2018 ◽  
Vol 1 ◽  
Author(s):  
Martina Pavlek ◽  
Miquel Arnedo ◽  
Fulvio Gasparo ◽  
Silvia Adrian

Because of their size, abundance and active predatory lifestyle, spiders of the family Dysderidae are among the most conspicuous creatures in the Dinaric caves. Historically, the interest for this group dates back to 1847, to the description of the first cave spider in the world, Stalita taenaria, and peaks in the middle of 20th century with the works of Joseph Kratochvíl and Christa L. Deeleman-Reinhold among others. However, after all these years, an explicit phylogenetic hypothesis about the family relationships is still missing and the taxonomy of some genera is a matter of debate. Dinaric cave representatives belong to two subfamilies: Rhodinae, with 13 species from five genera (Rhode, Stalita, Parastalita, Mesostalita and Stalitella) and Harpacteinae, with eight species from two genera (Folkia and Stalagtia). All species are considered troglobiotic and are Dinaric endemics, with Harpacteine restricted to the south part of the Dinaric Mountains and Rhodinae (with few exceptions) to the north part. Here, we present the results of a mutli-locus phylogenetic analysis of the family combining mitochondrial and nuclear genes of the focal group along with representatives of the other dysderid genera. Our data reveal a more complex taxonomic structure than currently recognized, with several instances of paraphyly, and uncover some overlooked diversity at the species level.

Symbiosis ◽  
2020 ◽  
Vol 80 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Ewa Sajnaga ◽  
Waldemar Kazimierczak

AbstractEntomopathogenic bacteria from the genera Photorhabdus and Xenorhabdus are closely related Gram-negative bacilli from the family Enterobacteriaceae (γ-Proteobacteria). They establish obligate mutualistic associations with soil nematodes from the genera Steinernema and Heterorhabditis to facilitate insect pathogenesis. The research of these two bacterial genera is focused mainly on their unique interactions with two different animal hosts, i.e. nematodes and insects. So far, studies of the mutualistic bacteria of nematodes collected from around the world have contributed to an increase in the number of the described Xenorhabdus and Photorhabdus species. Recently, the classification system of entomopatogenic nematode microsymbionts has undergone profound revision and now 26 species of the genus Xenorhabdus and 19 species of the genus Photorhabdus have been identified. Despite their similar life style and close phylogenetic origin, Photorhabdus and Xenorhabdus bacterial species differ significantly in e.g. the nematode host range, symbiotic strategies for parasite success, and arrays of released antibiotics and insecticidal toxins. As the knowledge of the diversity of entomopathogenic nematode microsymbionts helps to enable the use thereof, assessment of the phylogenetic relationships of these astounding bacterial genera is now a major challenge for researchers. The present article summarizes the main information on the taxonomy and evolutionary history of Xenorhabdus and Photorhabdus, entomopathogenic nematode symbionts.


1990 ◽  
Vol 3 (1) ◽  
pp. 145
Author(s):  
DJ Colgan

This paper is a review of the use of information regarding the presence of duplicate genes and their regulation in systematics. The review concentrates on data derived from protein electrophoresis and restriction fragment length polymorphism analysis. The appearance of a duplication in a subset of a group of species implies that the members of the subset belong to the same clade. Suppression of the duplication may render this clade apparently paraphyletic, but may itself be informative of relations within the lineage through patterns of loss of expression in all, or some tissues, or through restrictions of the formation of functional heteropolymers in polymeric enzymes. Examples are given of studies which have used such information to establish phylogenetic hypotheses at the family level, to identify an auto- or allo-polyploid origin of polyploid species and to determine whether there have been single or multiple origins of such species. The likelihood of homoplasy in the patterns of appearance and regulation of duplicates depends on the molecular basis of the duplication. In particular, the contrast between the expected consequences of tandem duplication and the expression of pseudogenes emphasises the value of determining the mechanism of the original duplication. Many instances of sporadic gene duplication are now known, and polyploidisation is a common event in the evolutionary history of both plants and animals. So the opportunities to discover duplicationrelated characters will arise in many systematic studies. A program is presented to increase the chances that such useful information will be recognisable during the studies.


1998 ◽  
Vol 8 (1) ◽  
pp. 21-41 ◽  
Author(s):  
Beatrice Forbes Manz

Temür has been many things to many people. He was nomad and city-builder, Turk and promoter of Persian culture, restorer of the Mongol order and warrior for the spread of Islam. One thing he was to all: a conqueror of unequalled scope, able to subdue both the vast areas of nomad power to the north and the centres of agrarian Islamic culture to the south. The history of his successors was one of increasing political fragmentation and economic stress. Yet they too won fame, as patrons over a period of brilliant cultural achievement in Persian and Turkic. Temür's career raises a number of questions. Why did he find it necessary to pile conquest upon conquest, each more ambitious than the last? Having conceived dreams of dominion, where did he get the power and money to fulfill them? When he died, what legacy did Temür leave to his successors and to the world which they tried to control? Finally, what was this world of Turk and Persian, and where did Temür and the Timurids belong within it?


Author(s):  
Jeannette Graulau

This chapter provides the mining history of the mountains of the rest of the world. It begins with England in which major silver discoveries took place in Bere Ferrers or Bere Ferris, a valley of the Tamar River in North Devon, southwest of Dartmoor, and at Combe Martin in the north after the mid-thirteenth century. However, English mines were challenging as they were physically distant from the central arteries of international trade of continental Europe and the commercial cities with continental catchment areas. This chapter also talks about silver mining that flourished in the Persian Province of Khorasan, the Samanid region of Transoxiana, and the Hindu Kush. These are the lands of the most spectacular mountain heights, where mountains piled up one behind another and mountain development assumes its grandest forms. It ends with mining history in India in which its mining exploits did not compete with the achievements of European mining regions. Mining in Zawar endured technical difficulties. Geologist Bagghi states that miners worked on hard siliceous quarzitic ore bodies, where drilling today calls for the use of tungsten carbide bits.


2021 ◽  
Vol 13 (2021/1) ◽  
Author(s):  
Krisztina Teleki

The 20th century brought different periods in the history of Mongolia including theocracy, socialism and democracy. This article describes what renouncing the world (especially the home and the family), taking ordination, and taking monastic vows meant at the turn of the 20th century and a century later. Extracts from interviews reveal the life of pre-novices, illustrating their family backgrounds, connections with family members after ordination, and support from and towards the family. The master-disciple relationship which was of great significance in Vajrayāna tradition, is also described. As few written sources are available to study monks’ family ties, the research was based on interviews recorded with old monks who lived in monasteries in their childhood (prior to 1937), monks who were ordained in 1990, and pre-novices of the current Tantric monastic school of Gandantegčenlin Monastery. The interviews revealed similarities and differences in monastic life in given periods due to historical reasons. Though Buddhism could not attain its previous, absolutely dominant role in Mongolia after the democratic changes, nowadays tradition and innovation exist in parallel.


2021 ◽  
pp. 229-241
Author(s):  
Maciej Rak

The article has three goals. The first is to present the history of research on Polish dialectal phrasematics. In particular, attention was paid to the last five years, i.e. the period 2015–2020. The works in question were ordered according to the dialectological key, taking into account the following dialects: Greater Polish, Masovian, Silesian, Lesser Polish, and the North and South-Eastern dialects. The second goal is to indicate the methodologies that have so far been used to describe dialectal phrasematics. Initially, component analysis was used, which was part of the structuralist research trend, later (more or less from the late 1980s) the ethnolinguistic approach, especially the description of the linguistic picture of the world, began to dominate. The third goal of the article is to provide perspectives. The author once again (as he did it in his earlier works) postulates the preparation of a dictionary of Polish dialectal phrasematics.


2018 ◽  
Vol 24 (2) ◽  
pp. 85-110
Author(s):  
Joanna Kulwicka-Kamińska

The religious writings of the Tatars constitute a valuable source for philological research due to the presence of heretofore unexplored grammatical and lexical layers of the north borderland Polish language of the 16th-20th centuries and due to the interference-related and transfer-related processes in the context of Slavic languages and Slavic-Oriental contacts. Therefore the basis for linguistic analyses is constituted by one of the most valuable monuments of this body of writing – the first translation of the Quran into a Slavic language in the world (probably representing the north borderland Polish language), which assumed the form of a tefsir. The source of linguistic analyses is constituted by the Olita tefsir, which dates back to 1723 (supplemented and corrected in the 19th century). On the basis of the material that was excerpted from this work the author presents both borderland features described in the subject literature and tries to point the new or only sparsely confirmed facts in the history of the Polish language, including the formation of the north borderland Polish language on the Belarusian substrate. Research involves all levels of language – the phonetic-phonological, morphological, syntactic and the lexical-semantic levels.


1993 ◽  
Vol 67 (4) ◽  
pp. 549-570 ◽  
Author(s):  
Bruce S. Lieberman

Phylogenetic parsimony analysis was used to classify the Siegenian–Eifelian “Metacryphaeus group” of the family Calmoniidae. Thirty-eight exoskeletal characters for 16 taxa produced a shortest-length cladogram with a consistency index of 0.49. A classification based on retrieving the structure of this cladogram recognizes nine genera: Typhloniscus Salter, Plesioconvexa n. gen., Punillaspis Baldis and Longobucco, Eldredgeia n. gen., Clarkeaspis n. gen., Malvinocooperella n. gen., Wolfartaspis Cooper, Plesiomalvinella Lieberman, Edgecombe, and Eldredge (used to represent the malvinellid clade), and Metacryphaeus Reed. The malvinellid clade is most closely related to a revised monophyletic Metacryphaeus. Typhloniscus is the basal member of the “Metacryphaeus group,” and the monotypic Wolfartaspis is sister to the clade containing the malvinellids and Metacryphaeus. Six new species are diagnosed: Punillaspis n. sp. A, “Clarkeaspis” gouldi, Clarkeaspis padillaensis, Malvinocooperella pregiganteus, Metacryphaeus curvigena, and Metacryphaeus branisai. Primitively, this group has South African and Andean affinities, and its evolutionary history suggests rapid diversification. In addition, evolutionary patterns in this group, and the distribution of character reversals, call into question certain notions about the nature of adaptive radiations. The distributions of taxa may answer questions about the number of marine transgressive/regressive cycles in the Emsian–Eifelian of the Malvinokaffric Realm.


2021 ◽  
Author(s):  
Keerthic Aswin ◽  
Srinivasan Ramachandran ◽  
Vivek T Natarajan

AbstractEvolutionary history of coronaviruses holds the key to understand mutational behavior and prepare for possible future outbreaks. By performing comparative genome analysis of nidovirales that contain the family of coronaviruses, we traced the origin of proofreading, surprisingly to the eukaryotic antiviral component ZNFX1. This common recent ancestor contributes two zinc finger (ZnF) motifs that are unique to viral exonuclease, segregating them from DNA proof-readers. Phylogenetic analyses indicate that following acquisition, genomes of coronaviruses retained and further fine-tuned proofreading exonuclease, whereas related families harbor substitution of key residues in ZnF1 motif concomitant to a reduction in their genome sizes. Structural modelling followed by simulation suggests the role of ZnF in RNA binding. Key ZnF residues strongly coevolve with replicase, and the helicase involved in duplex RNA unwinding. Hence, fidelity of replication in coronaviruses is a result of convergent evolution, that enables maintenance of genome stability akin to cellular proofreading systems.


2020 ◽  
Vol 2020 (12-1) ◽  
pp. 18-31
Author(s):  
Dmitry Pikalov ◽  
Vasilina Pikalova

The article is devoted to the analysis of the mechanism of creation of mythologemes in the system of the Soviet ideology of the early Soviet era. On the basis of materials from the Istparts of the North Caucasus, the authors study the construction of mythologemes and their impact on consciousness, when the comprehension of a new social reality took place through mythological images, which were based on the interpretation of the history of revolutionary events and the activities of historical figures. The technology of using mythologemes for manipulating mass consciousness, including for the purpose of introducing a new picture of the world into it, is considered.


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