The use of primitive character state distributions in the assessment of holophyly

1991 ◽  
Vol 39 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Mark Wilkinson
Keyword(s):  
Character State ◽  
Primitive Character

Systematic implications of achene micromorphology in Carex section Hymenochlaenae (Cyperaceae)

1990 ◽  
Vol 68 (3) ◽  
pp. 630-639 ◽  
Author(s):  
Marcia J. Waterway
Keyword(s):  
Epidermal Cells ◽  
Evolutionary Relationships ◽  
Character State ◽  
Primitive Character ◽  
Modified Silica ◽  
Surface Features ◽  
Parallel Development ◽  
Wall Structures ◽  
Epidermal Features

The structures of the achene epidermal cells and their included silica deposits are illustrated and described for 28 species that have been referred to Carex section Hymenochlaenae. On the basis of these epidermal features, there are anomalous species in nearly all of the subsections and sections that have been circumscribed by Kükenthal, Mackenzie, Ohwi, and Koyama. Furthermore, some species with nearly indistinguishable achene surface features have quite different overall morphologies and have traditionally been placed in different sections. Similarities in the structure of the silica deposits in the achene epidermal cells may result from the retention of the primitive character state in several different lineages or from parallel development of modified silica bodies or wall structures in different lineages. Levels of homoplasy appear to be too high to make these characters reliable indicators of evolutionary relationships in Carex section Hymenochlaenae.

scholarly journals Cambrian stem-group annelids and a metameric origin of the annelid head

2015 ◽  
Vol 11 (10) ◽  
pp. 20150763 ◽  
Author(s):  
Luke Parry ◽  
Jakob Vinther ◽  
Gregory D. Edgecombe
Keyword(s):  
Anterior Segment ◽  
Character State ◽  
Early Cambrian ◽  
Primitive Character ◽  
Burgess Shale ◽  
Crown Group ◽  
Middle Cambrian ◽  
Stem Group

The oldest fossil annelids come from the Early Cambrian Sirius Passet and Guanshan biotas and Middle Cambrian Burgess Shale. While these are among the best preserved polychaete fossils, their relationship to living taxa is contentious, having been interpreted either as members of extant clades or as a grade outside the crown group. New morphological observations from five Cambrian species include the oldest polychaete with head appendages, a new specimen of Pygocirrus from Sirius Passet, and an undescribed form from the Burgess Shale. We propose that the palps of Canadia are on an anterior segment bearing neuropodia and that the head of Phragmochaeta is formed of a segment bearing biramous parapodia and chaetae. The unusual anatomy of these taxa suggests that the head is not differentiated into a prostomium and peristomium, that palps are derived from a modified parapodium and that the annelid head was originally a parapodium-bearing segment. Canadia , Phragmochaeta and the Marble Canyon annelid share the presence of protective notochaetae, interpreted as a primitive character state subsequently lost in Pygocirrus and Burgessochaeta , in which the head is clearly differentiated from the trunk.

The oldest microsaur (Amphibia)

1991 ◽  
Vol 65 (2) ◽  
pp. 314-322 ◽  
Author(s):  
Robert L. Carroll ◽  
Paul Bybee ◽  
William D. Tidwell
Keyword(s):  
North American ◽  
Sister Group ◽  
Sister Group Relationship ◽  
Character State ◽  
Primitive Character ◽  
Fossil Plants ◽  
Shale Formation ◽  
Paleozoic Tetrapods

Utaherpeton franklini n. gen. and sp., from the Manning Canyon Shale Formation of Utah, is the oldest known microsaur. The horizon is dated as equivalent to the lowermost Namurian B of Europe (transitional from Upper Mississippian into lowermost Pennsylvanian in North American terminology) on the basis of a rich assemblage of fossil plants. The specimen may be tentatively placed within the suborder Microbrachomorpha. It exhibits the primitive character state for many microsaur features, but no synapomorphies are recognized that support a specific sister-group relationship between microsaurs and any other group of Paleozoic tetrapods.

A new specimen of Utatsusaurus (Reptilia: Ichthyosauria) from the Lower Triassic Sulphur Mountain Formation of British Columbia

1993 ◽  
Vol 30 (3) ◽  
pp. 486-490 ◽  
Author(s):  
Elizabeth L. Nicholls ◽  
Donald Brinkman
Keyword(s):  
British Columbia ◽  
Lower Triassic ◽  
Geographic Range ◽  
Character State ◽  
Primitive Character

An incomplete skull and mandible of the primitive ichthyosaur Utatsusaurus is described from the Lower Triassic Vega Phroso Member of the Sulphur Mountain Formation of British Columbia. The specimen contributes to our knowledge of the cranial anatomy of the genus, which was previously known primarily from postcranial material, and extends its geographic range to Canada. The presence of an isodont dentition in this primitive genus suggests that isodonty rather than heterodonty may be the primitive character state for the Ichthyosauria.

Evolution of Angiosperm Pollen: 8. Lamiids

2020 ◽  
Vol 105 (3) ◽  
pp. 323-376
Author(s):  
Li-E Yang ◽  
Lu Lu ◽  
Kevin S. Burgess ◽  
Hong Wang ◽  
De-Zhu Li
Keyword(s):  
Maximum Likelihood ◽  
Pollen Morphology ◽  
Pollen Size ◽  
State Transitions ◽  
Character State ◽  
Evolutionary Mechanisms ◽  
Pollen Characters ◽  
Exine Ornamentation ◽  
Shape Class ◽  
Pollen Character

Lamiids, a clade composed of approximately 15% of all flowering plants, contains more than 50,000 species dispersed across 49 families and eight orders (APG IV, 2016). This paper is the eighth in a series that analyzes pollen characters across angiosperms. We reconstructed a maximum likelihood tree based on the most recent phylogenetic studies for the Lamiids, comprising 150 terminal genera (including six outgroups) and covering all eight orders and 49 families within the clade. To illustrate pollen diversity across the Lamiids, pollen grains from 22 species (22 genera in 14 families) were imaged under light, scanning, and transmission electron microscopy. Eighteen pollen characters that were documented from previous publications, websites, and our new observations were coded and optimized onto the reconstructed phylogenetic tree using Fitch parsimony, maximum likelihood, and hierarchical Bayesian analysis. Pollen morphology of the Lamiids is highly diverse, particularly in shape class, pollen size, aperture number, endoaperture shape, supratectal element shape, and tectum sculpture. In addition, some genera show relatively high infrageneric pollen variation within the Lamiids: i.e., Coffea L., Jacquemontia Choisy, Justicia L., Pedicularis L., Psychotria L. nom. cons., Sesamum L., Stachytarpheta Vahl, and Veronica L. The plesiomorphic states for 16 pollen characters were inferred unambiguously, and 10 of them displayed consistent plesiomorphic states under all optimization methods. Seventy-one lineages at or above the family level are characterized by pollen character state transitions. We identified diagnostic character states for monophyletic clades and explored palynological evidence to shed light on unresolved relationships. For example, palynological evidence supports the monophyly of Garryales and Metteniusaceae, and sister relationships between Icacinaceae and Oncothecaceae, as well as between Vahliales and Solanales. The evolutionary patterns of pollen morphology found in this study reconfirm several previously postulated evolutionary trends, which include an increase in aperture number, a transition from equatorially arranged apertures to globally distributed ones, and an increase in exine ornamentation complexity. Furthermore, there is a significant correlation between pollen characters and a number of ecological factors, e.g., pollen size and pollination type, pollen ornamentation and pollination type, and shape class and plant growth form. Our results provide insight into the ecological, environmental, and evolutionary mechanisms driving pollen character state changes in the Lamiids.

scholarly journals The Evolution of Life Modes in Stictidaceae, with Three Novel Taxa

2021 ◽  
Vol 7 (2) ◽  
pp. 105
Author(s):  
Vinodhini Thiyagaraja ◽  
Robert Lücking ◽  
Damien Ertz ◽  
Samantha C. Karunarathna ◽  
Dhanushka N. Wanasinghe ◽  
...  
Keyword(s):  
New Species ◽  
Large Scale ◽  
Sequence Data ◽  
Large Subunit ◽  
Monte Carlo Sampling ◽  
Small Subunit ◽  
Sensu Stricto ◽  
Internal Transcribed Spacers ◽  
Character State ◽  
Phenotypic Data

Ostropales sensu lato is a large group comprising both lichenized and non-lichenized fungi, with several lineages expressing optional lichenization where individuals of the same fungal species exhibit either saprotrophic or lichenized lifestyles depending on the substrate (bark or wood). Greatly variable phenotypic characteristics and large-scale phylogenies have led to frequent changes in the taxonomic circumscription of this order. Ostropales sensu lato is currently split into Graphidales, Gyalectales, Odontotrematales, Ostropales sensu stricto, and Thelenellales. Ostropales sensu stricto is now confined to the family Stictidaceae, which includes a large number of species that are poorly known, since they usually have small fruiting bodies that are rarely collected, and thus, their taxonomy remains partly unresolved. Here, we introduce a new genus Ostropomyces to accommodate a novel lineage related to Ostropa, which is composed of two new species, as well as a new species of Sphaeropezia, S. shangrilaensis. Maximum likelihood and Bayesian inference analyses of mitochondrial small subunit spacers (mtSSU), large subunit nuclear rDNA (LSU), and internal transcribed spacers (ITS) sequence data, together with phenotypic data documented by detailed morphological and anatomical analyses, support the taxonomic affinity of the new taxa in Stictidaceae. Ancestral character state analysis did not resolve the ancestral nutritional status of Stictidaceae with confidence using Bayes traits, but a saprotrophic ancestor was indicated as most likely in a Bayesian binary Markov Chain Monte Carlo sampling (MCMC) approach. Frequent switching in nutritional modes between lineages suggests that lifestyle transition played an important role in the evolution of this family.

The Didache and St. Matthew's Gospel

1981 ◽  
Vol 34 (2) ◽  
pp. 109-120 ◽  
Author(s):  
J. M. Court
Keyword(s):  
Primitive Character ◽  
Widespread Agreement ◽  
Mutual Advantage

By widespread agreement the Didache is a riddle and an enigma, as to its chronological and geographical setting, its primitive character in matters of church order and theology, or its artificiality as a romantic contrivance or forgery. It is unlikely that the problem will be solved merely by reviewing the arguments yet again. But it may be possible to shed new light by concentrating on the tradition to which the Didache itself suggests that it belongs. An investigation of this tradition may also indicate a relationship between the Didache and St. Matthew's Gospel which is of mutual advantage in exegesis.

Phylogenetic and morphometric analyses of Eastern fluted-point forms

2015 ◽  
Author(s):  
◽  
Matthew T. Boulanger
Keyword(s):  
Material Culture ◽  
Selective Pressure ◽  
Cladistic Analysis ◽  
Eastern North America ◽  
Character State ◽  
State Change ◽  
University Of Missouri ◽  
Projectile Points ◽  
Morphometric Analyses ◽  
The University

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This dissertation constitutes two mutually complementary approaches to the study of Paleoindian material culture in eastern North America, ca. 13,500-10,500 calendar years before present. Archaeologists have long held that the East contains a substantially greater degree of morphological variation in Paleoindian point forms, though precisely why this is the case has rarely been explained. It is also unclear how many of the various point forms relate to each other in an evolutionary sense--which forms are derived from which, and why? Morphological analyses are conducted on a large sample of intact Paleoindian projectile points from across the East. I use paradigmatic classification to establish classes for use in a cladistic analysis to evaluate heritable continuity within the sample. Results of this analysis suggest that shape and form of Paleoindian projectile points changed in a more-or-less stochastic fashion across space, and evidence for strong selective pressure is limited. Findings concerning the process of character-state change suggest that some characters become fixed early in the evolution of points, whereas others appear to change frequently. The results of this study demonstrate that changes in Paleoindian projectile points can be explained within a cultural-evolution framework.

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