scholarly journals A completely resolved phylogenetic tree of British spiders (Arachnida: Araneae)

2021 ◽  
Vol 46 ◽  
pp. 1-51
Author(s):  
Rainer Breitling

The recent accumulation of increasingly densely sampled phylogenetic analyses of spiders has greatly advanced our understanding of evolutionary relationships within this group. Here, this diverse literature is reviewed and combined with earlier morphological analyses in an attempt to reconstruct the first fully resolved phylogeny for the spider fauna of the British Isles. The resulting tree highlights parts of the group where data are still too limited for a confident assessment of relationships, proposes a number of deviations from previously suggested phylogenetic hypotheses, and can serve as a framework for evolutionary and ecological interpretations of the biology of British spiders, as well as a starting point for future studies on a larger geographical scale.

2021 ◽  
Author(s):  
Rainer Breitling

AbstractThe recent accumulation of increasingly densely sampled phylogenetic analyses of spiders has greatly advanced our understanding of evolutionary relationships within this group. Here, this diverse literature is reviewed and combined with earlier morphological analyses in an attempt to reconstruct the first fully resolved phylogeny for the spider fauna of the British Isles. The resulting tree highlights parts of the group where data are still too limited for a confident assessment of relationships, proposes a number of deviations from previously suggested phylogenetic hypotheses, and can serve as a framework for evolutionary and ecological interpretations of the biology of British spiders, as well as a starting point for future studies on a larger geographical scale.


2019 ◽  
Vol 11 (10) ◽  
pp. 2824-2849 ◽  
Author(s):  
Paweł Mackiewicz ◽  
Adam Dawid Urantówka ◽  
Aleksandra Kroczak ◽  
Dorota Mackiewicz

Abstract Mitochondrial genes are placed on one molecule, which implies that they should carry consistent phylogenetic information. Following this advantage, we present a well-supported phylogeny based on mitochondrial genomes from almost 300 representatives of Passeriformes, the most numerous and differentiated Aves order. The analyses resolved the phylogenetic position of paraphyletic Basal and Transitional Oscines. Passerida occurred divided into two groups, one containing Paroidea and Sylvioidea, whereas the other, Passeroidea and Muscicapoidea. Analyses of mitogenomes showed four types of rearrangements including a duplicated control region (CR) with adjacent genes. Mapping the presence and absence of duplications onto the phylogenetic tree revealed that the duplication was the ancestral state for passerines and was maintained in early diverged lineages. Next, the duplication could be lost and occurred independently at least four times according to the most parsimonious scenario. In some lineages, two CR copies have been inherited from an ancient duplication and highly diverged, whereas in others, the second copy became similar to the first one due to concerted evolution. The second CR copies accumulated over twice as many substitutions as the first ones. However, the second CRs were not completely eliminated and were retained for a long time, which suggests that both regions can fulfill an important role in mitogenomes. Phylogenetic analyses based on CR sequences subjected to the complex evolution can produce tree topologies inconsistent with real evolutionary relationships between species. Passerines with two CRs showed a higher metabolic rate in relation to their body mass.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mario Vallejo-Marín ◽  
Jannice Friedman ◽  
Alex D. Twyford ◽  
Olivier Lepais ◽  
Stefanie M. Ickert-Bond ◽  
...  

AbstractImperfect historical records and complex demographic histories present challenges for reconstructing the history of biological invasions. Here, we combine historical records, extensive worldwide and genome-wide sampling, and demographic analyses to investigate the global invasion of Mimulus guttatus from North America to Europe and the Southwest Pacific. By sampling 521 plants from 158 native and introduced populations genotyped at >44,000 loci, we determined that invasive M. guttatus was first likely introduced to the British Isles from the Aleutian Islands (Alaska), followed by admixture from multiple parts of the native range. We hypothesise that populations in the British Isles then served as a bridgehead for vanguard invasions worldwide. Our results emphasise the highly admixed nature of introduced M. guttatus and demonstrate the potential of introduced populations to serve as sources of secondary admixture, producing novel hybrids. Unravelling the history of biological invasions provides a starting point to understand how invasive populations adapt to novel environments.


2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Wim Gorssen ◽  
Roel Meyermans ◽  
Steven Janssens ◽  
Nadine Buys

Abstract Background Runs of homozygosity (ROH) have become the state-of-the-art method for analysis of inbreeding in animal populations. Moreover, ROH are suited to detect signatures of selection via ROH islands and are used in other applications, such as genomic prediction and genome-wide association studies (GWAS). Currently, a vast amount of single nucleotide polymorphism (SNP) data is available online, but most of these data have never been used for ROH analysis. Therefore, we performed a ROH analysis on large medium-density SNP datasets in eight animal species (cat, cattle, dog, goat, horse, pig, sheep and water buffalo; 442 different populations) and make these results publicly available. Results The results include an overview of ROH islands per population and a comparison of the incidence of these ROH islands among populations from the same species, which can assist researchers when studying other (livestock) populations or when looking for similar signatures of selection. We were able to confirm many known ROH islands, for example signatures of selection for the myostatin (MSTN) gene in sheep and horses. However, our results also included multiple other ROH islands, which are common to many populations and not identified to date (e.g. on chromosomes D4 and E2 in cats and on chromosome 6 in sheep). Conclusions We are confident that our repository of ROH islands is a valuable reference for future studies. The discovered ROH island regions represent a unique starting point for new studies or can be used as a reference for future studies. Furthermore, we encourage authors to add their population-specific ROH findings to our repository.


Author(s):  
Małgorzata Robak ◽  

Despite many studies, the “check points” of metabolic regulation of citric acid (CA) secretion by the yeasts Y.lipolytica still remain unknown. In this manuscript, some possible aspects of strain dependent secretion as well as CA metabolism regulation were discussed. Keys enzymes’ activities, substrate concentration, affinity of the uptake systems, intracellular CA concentration and strains abilities were the main points taken into consideration. The direction for the future studies emerged from this review, mainly connected to cellular and mitochondrial citrate transport systems and cellular substrates transporters (glucose, fructose, glycerol, ethanol and acetate), give promising starting point for future efficient strain development.


2021 ◽  
pp. 1-28
Author(s):  
Yoshimasa Kumekawa ◽  
Haruka Fujimoto ◽  
Osamu Miura ◽  
Ryo Arakawa ◽  
Jun Yokoyama ◽  
...  

Abstract Harvestmen (Arachnida: Opiliones) are soil animals with extremely low dispersal abilities that experienced allopatric differentiation. To clarify the morphological and phylogenetic differentiation of the endemic harvestman Zepedanulus ishikawai (Suzuki, 1971) (Laniatores: Epedanidae) in the southern part of the Ryukyu Archipelago, we conducted molecular phylogenetic analyses and divergence time estimates based on CO1 and 16S rRNA sequences of mtDNA, the 28S rRNA sequence of nrDNA, and the external morphology. A phylogenetic tree based on mtDNA sequences indicated that individuals of Z. ishikawai were monophyletic and were divided into clade I and clade II. This was supported by the nrDNA phylogenetic tree. Although clades I and II were distributed sympatrically on all three islands examined (Ishigaki, Iriomote, and Yonaguni), heterogeneity could not be detected by polymerase chain reaction–restriction fragment length polymorphism of nrDNA, indicating that clades I and II do not have a history of hybridisation. Also, several morphological characters differed significantly between individuals of clade I and clade II. The longstanding isolation of the southern Ryukyus from the surrounding islands enabled estimation of the original morphological characters of both clades of Z. ishikawai.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7430
Author(s):  
Kumiko Matsui ◽  
Takanobu Tsuihiji

Background Desmostylia is a clade of extinct aquatic mammals with no living members. Today, this clade is considered belonging to either Afrotheria or Perissodactyla. In the currently-accepted taxonomic scheme, Desmostylia includes two families, 10 to 12 genera, and 13–14 species. There have been relatively few phylogenetic analyses published on desmostylian interrelationship compared to other vertebrate taxa, and two main, alternative phylogenetic hypotheses have been proposed in previous studies. One major problem with those previous studies is that the numbers of characters and OTUs were small. Methods In this study, we analyzed the phylogenetic interrelationship of Desmostylia based on a new data matrix that includes larger numbers of characters and taxa than in any previous studies. The new data matrix was compiled mainly based on data matrices of previous studies and included three outgroups and 13 desmostylian ingroup taxa. Analyses were carried out using five kinds of parsimonious methods. Results Strict consensus trees of the most parsimonious topologies obtained in all analyses supported the monophyly of Desmostylidae and paraphyly of traditional Paleoparadoxiidae. Based on these results, we propose phylogenetic definitions of the clades Desmostylidae and Paleoparadoxiidae based on common ancestry.


Author(s):  
Angelo Bonfanti

This chapter aims to theoretically examine effective surveillance management (ESM) during service encounters within the servicescape and provide a conceptual framework for the study of this topic in a service management perspective. It analyses antecedents, dimensions and effects of ESM. This study especially proposes as antecedents both improving customer service experience along with meeting customers' need for security and implementing a surveillance service-oriented strategy that includes secure and safe servicescape design, deterrent communication, and trained and motivated security staff. This chapter suggests also that the dimensions of ESM (customer-physical service environment encounters, customer-technological surveillance systems encounters, and customer-security staff encounters) contribute to enhancing service quality, experience quality, and staff productivity. The integration of these dimensions, antecedents, and effects create a theoretically grounded framework that can serve as a starting point for future studies about this topic in the field of service management.


2006 ◽  
Vol 04 (01) ◽  
pp. 59-74 ◽  
Author(s):  
YING-JUN HE ◽  
TRINH N. D. HUYNH ◽  
JESPER JANSSON ◽  
WING-KIN SUNG

To construct a phylogenetic tree or phylogenetic network for describing the evolutionary history of a set of species is a well-studied problem in computational biology. One previously proposed method to infer a phylogenetic tree/network for a large set of species is by merging a collection of known smaller phylogenetic trees on overlapping sets of species so that no (or as little as possible) branching information is lost. However, little work has been done so far on inferring a phylogenetic tree/network from a specified set of trees when in addition, certain evolutionary relationships among the species are known to be highly unlikely. In this paper, we consider the problem of constructing a phylogenetic tree/network which is consistent with all of the rooted triplets in a given set [Formula: see text] and none of the rooted triplets in another given set [Formula: see text]. Although NP-hard in the general case, we provide some efficient exact and approximation algorithms for a number of biologically meaningful variants of the problem.


2012 ◽  
Vol 34 (1) ◽  
pp. 18 ◽  
Author(s):  
Thomas J. McGreevy ◽  
Lisa Dabek ◽  
Thomas P. Husband

New Guinea tree kangaroos (Dendrolagus spp.) are unique arboreal macropodid marsupials mainly listed as critically endangered or endangered. The molecular systematics of Dendrolagus has not been fully resolved and is critical for the accurate identification of species and their evolutionary relationships. Matschie’s tree kangaroo (D. matschiei) and Goodfellow’s tree kangaroo (D. goodfellowi buergersi) share numerous morphological, physiological, and behavioural traits. We analysed the partial mitochondrial DNA cytochrome b gene for D. matschiei (n = 67), D. g. buergersi (n = 8), D. goodfellowi unidentified ssp. (n = 8), golden-mantled tree kangaroo (D. g. pulcherrimus; n = 1), and two additional New Guinea Dendrolagus taxa to determine whether D. matschiei and D. g. buergersi are sister taxa. D. matschiei and D. g. buergersi were not placed as sister taxa in our phylogenetic analyses; however, we were unable to analyse a known sample from a D. g. goodfellowi. We found initial genetic evidence that D. matschiei and the Lowland tree kangaroo (D. spadix) are sister taxa – they may have diverged after the formation of the Huon Peninsula of Papua New Guinea. Our results also support the elevation of D. g. pulcherrimus to a full species. An improved understanding of Dendrolagus molecular systematics will contribute substantially to their conservation.


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