The Lophophorate Condition

1981 ◽  
Vol 5 ◽  
pp. 190-204 ◽  
Author(s):  
James W. Valentine
Keyword(s):  
Special Interest ◽  
Evolutionary History ◽  
Distribution Patterns ◽  
Comparative Approach ◽  
Research Areas ◽  
History Of ◽  
Feeding Systems

Most major topics that bear on the lophophorate condition have been ably treated in preceding contributions for either the Bryozoa or Brachiopoda. Accordingly I shall attempt a comparative approach, first characterizing the lophophorates as a whole and then contrasting the groups with an eye towards the evolutionary implications of resemblances and differences. To set a practical target I shall attempt contrasts between the feeding systems, because they seem to be particularly important to the present habits, habitats and distribution patterns of these groups. From this approach, questions naturally arise as to the evolutionary history of the lophophorates and in particular of extinct types of Brachiopoda for which modern analogues are unknown; these problems form potential research areas of special interest. To conserve space I have tried where possible to cite only more recent and/or general works that themselves contain ample references. I have assumed that by this point in the volume the reader will be acquainted with the gross morphology of bryozoans and brachiopods and with the major descriptive terms applied thereto. Because phoronids are not specifically covered in other contributions, I have included a wider range of phoronid references including some historically important works.

scholarly journals Distributions and phylogeographic data of rheophilic freshwater fishes provide evidences on the geographic extension of a central-brazilian amazonian palaeoplateau in the area of the present day Pantanal Wetland

2013 ◽  
Vol 11 (2) ◽  
pp. 319-326 ◽  
Author(s):  
Alexandre C. Ribeiro ◽  
Rodrigo M. Jacob ◽  
Ronnayana R. S. R. Silva ◽  
Flávio C. T. Lima ◽  
Daniela C. Ferreira ◽  
...  
Keyword(s):  
Molecular Analysis ◽  
Evolutionary History ◽  
Distribution Patterns ◽  
Sister Group ◽  
Freshwater Fishes ◽  
Drainage Basins ◽  
Vicariant Event ◽  
Shared History ◽  
History Of ◽  
Pantanal Wetland

The analysis of the distribution patterns presented by examples of freshwater fishes restricted to headwater habitat: the anostomid Leporinus octomaculatus, the characins Jubiaba acanthogaster, Oligosarcus perdido, Moenkhausia cosmops, Knodus chapadae, Planaltina sp., the loricariid Hypostomus cochliodon, and the auchenipterid Centromochlus sp. provided evidences of a relatively recent shared history between the highlands of the upper rio Paraguay and adjoining upland drainage basins. Restricted to headwater of the uplands in the upper rio Paraguay and adjoining basins, these species provide biological evidence of the former extension of the central Brazilian plateau before the origin of the Pantanal Wetland. Disjunction took place due to an ecological barrier to these rheophilic taxa represented tectonic subsidence related to the origin of the Pantanal Wetland. Molecular analysis of Jubiaba acanthogaster revealed that the sample from the upper rio Xingu basin are the sister-group of a clade that includes samples from the upper rio Arinos (upper rio Tapajós) plus the upper rio Paraguay basin, supporting the assumption that the origin of the upper rio Paraguay basin causing vicariance between this basin and the upper rio Tapajós is the least vicariant event in the evolutionary history of the group.

scholarly journals Does relaxing the infinite sites assumption give better tumor phylogenies? An ILP-based comparative approach

2017 ◽  
Author(s):  
Paola Bonizzoni ◽  
Simone Ciccolella ◽  
Gianluca Della Vedova ◽  
Mauricio Soto
Keyword(s):  
Evolutionary History ◽  
Cancer Genomics ◽  
Fundamental Problem ◽  
Comparative Approach ◽  
Cancer Evolution ◽  
Perfect Phylogeny ◽  
New Approach ◽  
Recurrent Mutations ◽  
History Of ◽  
The One

AbstractMost of the evolutionary history reconstruction approaches are based on the infinite site assumption, which is underlying the Perfect Phylogeny model and whose main consequence is that acquired mutation can never lost. This results in the clonal model used to explain cancer evolution. Some recent results gives a strong evidence that recurrent and back mutations are present in the evolutionary history of tumors [5,21], thus showing that more general models then the Perfect Phylogeny are required. We propose a new approach that incorporates the possibility of losing a previously acquired mutation, extending the Persistent Phylogeny model [1].We exploit our model to provide an ILP formulation of the problem of reconstructing trees on mixed populations, where the input data consists of the fraction of cells in a set of samples that have a certain mutation. This is a fundamental problem in cancer genomics, where the goal is to study the evolutionary history of a tumor. An experimental analysis shows the usefulness of allowing mutation losses, by studying some real and simulated datasets where our ILP approach provides a better interpretation than the one obtained under perfect phylogeny assumption. Finally, we show how to incorporate multiple back mutations and recurrent mutations in our model.

scholarly journals Molecular phylogenetics and evolutionary history of the endemic land snail genus Everettia in northern Borneo

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9416 ◽  
Author(s):  
Thor-Seng Liew ◽  
Mohammad Effendi Marzuki ◽  
Menno Schilthuizen ◽  
Yansen Chen ◽  
Jaap J. Vermeulen ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Molecular Phylogenetics ◽  
Divergence Time ◽  
Distribution Patterns ◽  
Land Snail ◽  
High Elevation ◽  
Mountain Range ◽  
Climatic Fluctuations ◽  
Species Diversification ◽  
History Of

Borneo has gone through dramatic changes in geology and topography from the early Eocene until the early Pliocene and experienced climatic cycling during the Pleistocene. However, how these changes have shaped the present-day patterns of high diversity and complex distribution are still poorly understood. In this study, we use integrative approaches by estimating phylogenetic relationships, divergence time, and current and past niche suitability for the Bornean endemic land snail genus Everettia to provide additional insight into the evolutionary history of this genus in northern Borneo in the light of the geological vicariance events and climatic fluctuations in the Pleistocene. Our results show that northern Borneo Everettia species belong to two deeply divergent lineages: one contains the species that inhabit high elevation at the central mountain range, while the other contains lowland species. Species diversification in these lineages has taken place before the Pliocene. Climate changes during the Pleistocene did not play a significant role in species diversification but could have shaped contemporary species distribution patterns. Our results also show that the species-rich highland habitats have acted as interglacial refugia for highland species. This study of a relatively sedentary invertebrate supports and enhances the growing understanding of the evolutionary history of Borneo. Species diversification in Everettia is caused by geological vicariance events between the early Miocene and the Pliocene, and the distribution patterns were subsequently determined by climatic fluctuations in the Pleistocene.

Polyploidy and possible implications for the evolutionary history of some Australian Danthonieae

2010 ◽  
Vol 58 (1) ◽  
pp. 23 ◽  
Author(s):  
C. Waters ◽  
B. G. Murray ◽  
G. Melville ◽  
D. Coates ◽  
A. Young ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Potential Role ◽  
New South ◽  
Ecological Factors ◽  
Distribution Patterns ◽  
Low Frequencies ◽  
Rapid Speciation ◽  
South Wales ◽  
History Of

Polyploidy is a widespread feature of some plants that allows for rapid speciation and occurs widely in Poaceae. However, there have been few studies of Australian native grasses reporting the distribution patterns of cytotypes and examining the potential role of different cytotypes in adaptation. We determined chromosome number for 48, 113, 8, 43 and 33 plants of Austrodanthonia bipartita (Link) H.P.Linder, A. caespitosa (Gaudich.) H.P.Linder, A. eriantha (Lindl.) H.P.Linder, A. fulva (Vickery) H.P.Linder and A. setacea (R.Br.) H.P.Linder, respectively, representing 28 wild populations collected in central western New South Wales. A widespread distribution is reported for tetraploids (2n = 48), whereas diploids (2n = 24) and a limited number of hexaploids (2n = 72) appear to be associated with northern and western populations. In all populations, coexistent cytotypes were found, although tetraploids were the most widespread cytotype for the most commonly occurring species, A. caespitosa. The occurrence of low frequencies of putative intermediate cytotypes, particularly triploids, in all five species provides evidence for inter-specific hybridisation and/or intra-specific crossing between cytotypes. The lack of common ecological factors (climate, edaphic or micro-site) that clearly distinguish diploid from tetraploid A. caespitosa plants provides further evidence for hybridisation between cytological races of this species.

Historical biogeography of the lichenized fungal genus Hypotrachyna (Parmeliaceae, Ascomycota): insights into the evolutionary history of a pantropical clade

2018 ◽  
Vol 50 (3) ◽  
pp. 283-298 ◽  
Author(s):  
Paloma CUBAS ◽  
H. Thorsten LUMBSCH ◽  
Ruth DEL PRADO ◽  
Zuzana FERENCOVA ◽  
Nestor L. HLADUN ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Phylogenetic Analyses ◽  
Distribution Patterns ◽  
Historical Biogeography ◽  
Long Distance ◽  
Ancestral Area ◽  
Molecular Evolutionary Rates ◽  
History Of ◽  
Nuclear Its ◽  
Distinct Distribution

AbstractHypotrachyna is a speciose genus of primarily tropical and oceanic lichen-forming fungi. It includes species with distinct distribution patterns, such as pantropical, restricted and disjunct species. We used a dataset of mitochondrial SSU, nuclear ITS and LSU ribosomal DNA from 89 specimens to study the historical biogeography of the genus. We employed Bayesian and maximum likelihood approaches for phylogenetic analyses, a likelihood-based approach to ancestral area estimation, and a Bayesian approach to estimate divergence times of major lineages within the genus based on molecular evolutionary rates for ITS and a secondary calibration point at the Hypotrachyna clade – Parmeliopsis split. Our analyses suggest that the genus might have originated in the Neotropics during the Eocene and that the split of major lineages happened primarily during the Eocene and Oligocene. The major diversification within those clades is estimated to have occurred during the Miocene. Pantropical species distributions are explained by long-distance dispersal. A number of currently accepted species were found to be non-monophyletic, illustrating that the delimitation of species in the genus needs attention.

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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