Molecular systematics of Australian Calotis (Asteraceae: Astereae)

2006 ◽  
Vol 19 (2) ◽  
pp. 155 ◽  
Author(s):  
K. Watanabe ◽  
K. Kosuge ◽  
R. Shimamura ◽  
N. Konishi ◽  
K. Taniguchi
Keyword(s):  
Evolutionary History ◽  
Life Form ◽  
Arid Zone ◽  
Its Region ◽  
Base Number ◽  
Multiple Origins ◽  
Matk Gene ◽  
History Of ◽  
Ancestral States ◽  
Generic Relationships

The intra-generic relationships of the Australian genus Calotis, with various chromosome base numbers from x = 8 to x = 4, were examined by the comparison of nucleotide sequences of the complete ITS region of nuclear rDNA and of the matK gene of chloroplast DNA. Within a monophyletic Calotis, four lineages were identified. Reconstruction of ancestral states suggests that the chromosome base number for Calotis is x = 8. Dysploidal reductions in chromosome base number from x = 8 to x = 7 and from x = 8 to x = 5 or 4 have occurred independently at least three times. Lower base numbers of x = 7, 5, and 4 are found predominantly in the arid and semi-arid zone species of Central and Western Australia. Total karyotypic length (genome size) is greater in perennials than in annuals within the genus Calotis. The elaborated pappus and surface structures of cypsela, and life form of species seem to be homoplasous with multiple origins in the evolutionary history of the lineage.

Molecular systematics of Australian Podolepis (Asteraceae: Gnaphalieae): evidence from DNA sequences of the nuclear ITS region and the chloroplast matK gene

2000 ◽  
Vol 13 (5) ◽  
pp. 709 ◽  
Author(s):  
N. Konishi ◽  
K. Watanabe ◽  
K. Kosuge
Keyword(s):  
Dna Sequences ◽  
Its Region ◽  
Chromosomal Evolution ◽  
Internal Transcribed Spacers ◽  
Nuclear Ribosomal Dna ◽  
Base Number ◽  
Monophyletic Clade ◽  
Matk Gene ◽  
Nuclear Its ◽  
Generic Relationships

The generic circumscription and intra-generic relationships of the genus Podolepis Labill., with various chromosome numbers from n = 12 to n = 3, were examined by sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA and the matK gene of chloroplast DNA. The topology of the ITS tree for 17 species and the matK tree for 18 species of the genus Podolepis sensu Davis (1957) and Anderberg (1991) and 15 taxa from eight related genera (Anderberg 1989, 1991, 1994) are basically concordant. Except for P. georgei Diels andP. kendallii F.Muell., parsimony analyses support the monophyly of the genus Podolepis sensu Davis (1957) and Anderberg (1991). The genera of Asteridea Lindl. and Pterochaeta Steetz are sisters toPodolepis in the combined tree based on the ITS and matK sequences. Within the monophyletic clade of the genus Podolepis, three lineages are identified. The chromosome base number of x = 12 may be ancestral in the genus Podolepis. The dysploidal reduction in chromosome number from n = 12 to n = 10 and 9, from n = 12 to n = 8 and 7, and from n = 12 to n = 11 and 3 in three lineages, respectively, is the primary mode of chromosomal evolution in this genus. Total karyotypic length (= genome size) is much greater in perennials than in annuals within the genus Podolepis. The number of pappus bristles on outer female florets tends to decrease and they are absent in some annuals of this genus, while myxogenic cells on the pericarp become prominent.

The origins and evolutionary history of xerophytic vegetation in Australia

2020 ◽  
Vol 68 (3) ◽  
pp. 195 ◽  
Author(s):  
Margaret Byrne ◽  
Daniel J. Murphy
Keyword(s):  
Evolutionary History ◽  
Arid Zone ◽  
Major Change ◽  
Significant Component ◽  
Multiple Origins ◽  
Geographic Structure ◽  
Speciation Rates ◽  
History Of ◽  
Australian Flora ◽  
Plant Families

The xeromorphic vegetation is a significant component of the Australian flora and phylogenetic and phylogeographic analysis of xeromorphic plants provides a basis for understanding the origins and evolutionary history of the Australian vegetation. Here we expand on previous reviews of the origins and maintenance of the Australian flora with an emphasis on the xeromorphic component. Phylogenetic evidence supports fossil evidence for evolution of sclerophyll and xeromorphic vegetation from the Eocene with lineages becoming more common in the Oligocene and Miocene, a time of major change in climate and vegetation in Australia. Phylogenetic evidence supports the mesic biome as ancestral to the arid zone biome in Australia in phylogenies of key groups. The diversification and radiation of Australian species shows single origins of xeromorphic group mainly at deeper levels in phylogenies as well as multiple origins of arid occurring species at shallower levels. Divergence across the Nullarbor is also evident and speciation rates in south-western Australia were higher than in the south-east in several plant families. Estimates of timing of diversification generally show either constant rates of diversification or increased diversification from the mid to late Miocene. Phylogeographic studies consistently demonstrate high localised genetic diversity and geographic structure in xeromorphic species occupying both mesic and arid biomes.

Systematic evidence from gene duplication and regulation

1990 ◽  
Vol 3 (1) ◽  
pp. 145
Author(s):  
DJ Colgan
Keyword(s):  
Gene Duplication ◽  
Evolutionary History ◽  
Tandem Duplication ◽  
Fragment Length Polymorphism ◽  
Duplicate Genes ◽  
Polymorphism Analysis ◽  
Multiple Origins ◽  
The Family ◽  
History Of ◽  
Phylogenetic Hypotheses

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.

scholarly journals RIP mutated ITS genes in populations of Ophiocordyceps sinensis and their implications for molecular systematics

IMA Fungus ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Yi Li ◽  
Lan Jiang ◽  
Ke Wang ◽  
Hai-Jun Wu ◽  
Rui-Heng Yang ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Large Scale ◽  
Its Region ◽  
Wide Distribution ◽  
Specific Primers ◽  
Ophiocordyceps Sinensis ◽  
Single Genome ◽  
History Of ◽  
Geographic Populations ◽  
Internal Transcribed Spacer Sequences

Abstract Different hypotheses have been proposed to interpret the observed unusual ITS (internal transcribed spacer) sequences in Ophiocordyceps sinensis. The coexistence of diverged ITS paralogs in a single genome was previously shown by amplifying the ITS region from mono-ascospore isolates using specific primers designed for different ITS paralog groups. Among those paralogs, are AT-biased ITS sequences which were hypothesized to result from repeat-induced point mutation (RIP). This is a process that detects and mutates repetitive DNA and frequently leads to epigenetic silencing, and these mutations have been interpreted as pseudogenes. Here we investigate the occurrence and frequency of ITS pseudogenes in populations of O. sinensis using large-scale sampling, and discusses the implications of ITS pseudogenes for fungal phylogenetic and evolutionary studies. Our results demonstrate a wide distribution of ITS pseudogenes amongst different geographic populations, and indicate how ITS pseudogenes can contribute to the reconstruction of the evolutionary history of the species.

scholarly journals Pervasive contingency and entrenchment in a billion years of Hsp90 evolution

2018 ◽  
Vol 115 (17) ◽  
pp. 4453-4458 ◽  
Author(s):  
Tyler N. Starr ◽  
Julia M. Flynn ◽  
Parul Mishra ◽  
Daniel N. A. Bolon ◽  
Joseph W. Thornton
Keyword(s):  
Evolutionary History ◽  
Heat Shock Protein 90 ◽  
General Effect ◽  
Ancestral State ◽  
Atpase Domain ◽  
Internal Constraints ◽  
Fitness Effects ◽  
History Of ◽  
Evolutionary Trajectories ◽  
Ancestral States

Interactions among mutations within a protein have the potential to make molecular evolution contingent and irreversible, but the extent to which epistasis actually shaped historical evolutionary trajectories is unclear. To address this question, we experimentally measured how the fitness effects of historical sequence substitutions changed during the billion-year evolutionary history of the heat shock protein 90 (Hsp90) ATPase domain beginning from a deep eukaryotic ancestor to modern Saccharomyces cerevisiae. We found a pervasive influence of epistasis. Of 98 derived amino acid states that evolved along this lineage, about half compromise fitness when introduced into the reconstructed ancestral Hsp90. And the vast majority of ancestral states reduce fitness when introduced into the extant S. cerevisiae Hsp90. Overall, more than 75% of historical substitutions were contingent on permissive substitutions that rendered the derived state nondeleterious, became entrenched by subsequent restrictive substitutions that made the ancestral state deleterious, or both. This epistasis was primarily caused by specific interactions among sites rather than a general effect on the protein’s tolerance to mutation. Our results show that epistasis continually opened and closed windows of mutational opportunity over evolutionary timescales, producing histories and biological states that reflect the transient internal constraints imposed by the protein’s fleeting sequence states.

Extreme genetic diversity among springtails (Collembola) in subterranean calcretes of arid Australia

Genome ◽  
2020 ◽  
pp. 1-15
Author(s):  
Michelle T. Guzik ◽  
Mark I. Stevens ◽  
Steven J.B. Cooper ◽  
William F. Humphreys ◽  
Andrew D. Austin
Keyword(s):  
Genetic Diversity ◽  
New Species ◽  
Evolutionary History ◽  
Arid Zone ◽  
Coi Gene ◽  
Aquatic Species ◽  
Climatic Oscillations ◽  
History Of ◽  
Multiple Levels ◽  
Complex Evolutionary History

The subterranean islands hypothesis for calcretes of the Yilgarn region in Western Australia applies to many stygobitic (subterranean–aquatic) species that are “trapped” evolutionarily within isolated aquifers due to their aquatic lifestyles. In contrast, little is known about the distribution of terrestrial–subterranean invertebrates associated with the calcretes. We used subterranean Collembola from the Yilgarn calcretes to test the hypothesis that troglobitic species, those inhabiting the subterranean unsaturated (non-aquatic) zone of calcretes, are also restricted in their distribution and represent reciprocally monophyletic and endemic lineages. We used the barcoding fragment of the mtDNA cytochrome c oxidase subunit 1 (COI) gene from 183 individuals to reconstruct the phylogenetic history of the genus Pseudosinella Schäffer (Collembola, Lepidocyrtidae) from 10 calcretes in the Yilgarn. These calcretes represent less than 5% of the total possible calcretes in this region, yet we show that their diversity for subterranean Collembola comprises a minimum of 25 new species. Regionally, multiple levels of diversity exist in Pseudosinella, indicative of a complex evolutionary history for this genus in the Yilgarn. These species have probably been impacted by climatic oscillations, facilitating their dispersal across the landscape. The results represent a small proportion of the undiscovered diversity in Australia’s arid zone.

scholarly journals Evolutionary history of sexual differentiation mechanism in insects

2021 ◽  
Author(s):  
Yasuhiko Chikami ◽  
Miki Okuno ◽  
Atsushi Toyoda ◽  
Takehiko Itoh ◽  
Teruyuki Niimi
Keyword(s):  
Sexual Differentiation ◽  
Evolutionary History ◽  
Sister Group ◽  
Protein Motif ◽  
Sexual Dimorphisms ◽  
History Of ◽  
Alternatively Spliced ◽  
The Common ◽  
Ancestral States ◽  
Female Specific

AbstractGain of alternative splicing gives rise to functional diversity in proteins and underlies the complexity and diversity of biological aspects. However, it is still not fully understood how alternatively spliced genes develop the functional novelty. To this end, we infer the evolutionary history of the doublesex gene, the key transcriptional factor in the sexual differentiation of arthropods. doublesex is controlled by sex-specific splicing and promotes both male and female differentiation in some holometabolan insects. In contrast, doublesex promotes only male differentiation in some hemimetabolan insects. Here, we investigate ancestral states of doublesex using Thermobia domestica belonging to Zygentoma, the sister group of winged insects. We find that doublesex of T. domestica expresses sex-specific isoforms but is only necessary for male differentiation of sexual morphology. This result ensures the hypothesis that doublesex was initially only used to promote male differentiation during insect evolution. However, T. domestica doublesex has a short female-specific region and upregulates the expression of vitellogenin homologs in females, suggesting that doublesex may have already controlled some aspects of feminization in the common ancestor of winged insects. Reconstruction of the ancestral sequence and prediction of the protein structure show that the female-specific isoform of doublesex has a long C-terminal disordered region in holometabolan insects, but not in non-holometabolan species. We propose that doublesex acquired a female-specific isoform and then underwent a change in the protein motif structure, which became essential for female differentiation in sexual dimorphisms.

scholarly journals Laticifers in Sapindaceae: Structure, Evolution and Phylogenetic Importance

2021 ◽  
Vol 11 ◽  
Author(s):  
Maria Camila Medina ◽  
Mariane S. Sousa-Baena ◽  
Erika Prado ◽  
Pedro Acevedo-Rodríguez ◽  
Pedro Dias ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Evolutionary History ◽  
Likelihood Estimation ◽  
Structure Evolution ◽  
Key Innovation ◽  
The Family ◽  
Ancestral States ◽  
Stochastic Mapping ◽  
Generic Relationships

Laticifer occurrence and structure are poorly known in Sapindaceae. Occurrence is likely underestimated owing to the low production of latex in most species. We investigated 67 species from 23 genera of Sapindaceae to verify laticifer occurrence and their structural, developmental and chemical features, as well as their evolutionary history in the family. Shoots were collected from herbarium and fresh specimens for histological analyses. Three characters derived from laticifer features were coded and their ancestral states reconstructed through Bayesian stochastic mapping and maximum likelihood estimation. Only articulated non-anastomosing laticifers were found in Sapindaceae. Laticifers differentiate early during shoot development and are found in the cortex, phloem, and pith. Latex is mostly composed of lipids. Callose and suberin were detected in laticifer cell walls in some genera. Reconstruction of laticifer ancestral states showed that laticifers are present in most clades of Sapindaceae with some reversals. Callose in the laticifer cell wall was found exclusively in Serjania and Paullinia (tribe Paullinieae), a character regarded as independently derived. Occurrence of laticifers in Sapindaceae is broader than previously reported. Articulated non-anastomosing laticifers had five independent origins in Sapindaceae with some secondary losses, occurring in five out of six genera of Paullinieae and 10 other genera outside Paullinieae. Particularly, callose in the laticifer cell wall evolved independently twice in the family, and its occurrence may be interpreted as a key-innovation that promoted the diversification of Paullinia and Serjania. Our study suggests that laticifer characters may be useful in understanding the generic relationships within the family.

scholarly journals Evolutionary history of mental glands in turtles reveals a single origin in an aquatic ancestor and recurrent losses independent of macrohabitat

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alejandro Ibáñez ◽  
Uwe Fritz ◽  
Markus Auer ◽  
Albert Martínez-Silvestre ◽  
Peter Praschag ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Ecological Niches ◽  
Evolutionary Trends ◽  
Chemical Signaling ◽  
Signaling Systems ◽  
Morphological Complexity ◽  
Single Origin ◽  
History Of ◽  
Ancestral States ◽  
The Impact

AbstractDespite the relevance of chemical communication in vertebrates, comparative examinations of macroevolutionary trends in chemical signaling systems are scarce. Many turtle and tortoise species are reliant on chemical signals to communicate in aquatic and terrestrial macrohabitats, and many of these species possess specialized integumentary organs, termed mental glands (MGs), involved in the production of chemosignals. We inferred the evolutionary history of MGs and tested the impact of macrohabitat on their evolution. Inference of ancestral states along a time-calibrated phylogeny revealed a single origin in the ancestor of the subclade Testudinoidea. Thus, MGs represent homologous structures in all descending lineages. We also inferred multiple independent losses of MGs in both terrestrial and aquatic clades. Although MGs first appeared in an aquatic turtle (the testudinoid ancestor), macrohabitat seems to have had little effect on MG presence or absence in descendants. Instead, we find clade-specific evolutionary trends, with some clades showing increased gland size and morphological complexity, whereas others exhibiting reduction or MG loss. In sister clades inhabiting similar ecological niches, contrasting patterns (loss vs. maintenance) may occur. We conclude that the multiple losses of MGs in turtle clades have not been influenced by macrohabitat and that other factors have affected MG evolution.

Elaborating the role of reflection and individual differences in the study of folk-economic beliefs

2018 ◽  
Vol 41 ◽  
Author(s):  
Kevin Arceneaux
Keyword(s):  
Decision Making ◽  
Individual Differences ◽  
Cognitive Processes ◽  
Evolutionary History ◽  
Behavioral Responses ◽  
History Of ◽  
Economic Beliefs

AbstractIntuitions guide decision-making, and looking to the evolutionary history of humans illuminates why some behavioral responses are more intuitive than others. Yet a place remains for cognitive processes to second-guess intuitive responses – that is, to be reflective – and individual differences abound in automatic, intuitive processing as well.

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