scholarly journals Embryology of Eusideroxylon (Cryptocaryeae, Lauraceae) and character evolution in the family

2006 ◽  
Vol 150 (2) ◽  
pp. 187-201 ◽  
Author(s):  
YUKITOSHI KIMOTO ◽  
NANDA UTAMI ◽  
HIROSHI TOBE
Keyword(s):  
Character Evolution ◽  
The Family

scholarly journals Phylogenetic Analysis of Wing Feather Taxis in Birds: Macroevolutionary Patterns of Genetic Drift?

The Auk ◽  
2002 ◽  
Vol 119 (4) ◽  
pp. 943-954 ◽  
Author(s):  
Kimberly S. Bostwick ◽  
Matthew J. Brady
Keyword(s):  
Genetic Drift ◽  
Dna Hybridization ◽  
Character Evolution ◽  
Adaptive Function ◽  
Ecological Traits ◽  
Wing Feather ◽  
The Family ◽  
Tree Length ◽  
Preliminary Consideration ◽  
Selective Regime

Abstract Most recent research on character evolution attempts to identify either (1) homology or homoplasy (systematic use of the term character), or (2) the adaptive function or selective regime underlying the origin of a character (“adaptationist” use of the term character). There have been relatively few serious considerations or examples of neutral character evolution above the molecular level. Wing feather taxis in birds, the presence or absence of the fifth secondary feather, provides an intriguing possible example of nonadaptive character evolution. We examine the phylogenetic pattern of wing feather taxis among birds to (1) determine its polarity in modern birds (Neornithes), (2) hypothesize the frequency and taxonomic locations of changes in the taxic state, (3) test whether taxis is relatively labile or inert phylogenetically, and (4) allow preliminary consideration of whether adaptive or selectively neutral processes have produced those patterns. Minimum tree length necessary to explain the distribution of wing feather taxis was calculated at the family level using Sibley and Ahlquist's DNA–DNA hybridization tree (1990). Parsimony analysis indicates that the eutaxic condition (fifth secondary present) is ancestral in modern birds, and that diastataxy (fifth secondary absent) has originated independently at least 7 times and reversed to the eutaxic condition on at least 13 occasions within modern birds. Despite multiple independent origins and reversals, wing feather taxis is extremely conserved throughout the tree, such that one or the other state completely characterizes many large multiordinal or multifamilial clades. Lack of obvious correlations with morphological and ecological traits suggest that no single adaptive scenario will explain the evolution of wing feather taxis. Instead, the biological details and phylogenetic patterns make nonadaptive, or selectively neutral evolutionary processes, such as genetic drift, an equally if not more plausible explanation for the distribution of wing feather taxis.

Phylogenetic relationships of the subfamily Pyrgulinae (Gastropoda: Caenogastropoda: Hydrobiidae) with emphasis on the genus Dianella Gude, 1913

Zootaxa ◽  
2005 ◽  
Vol 891 (1) ◽  
pp. 1 ◽  
Author(s):  
Magdalena Szarowska ◽  
Andrzej Falniowski ◽  
FRANK Riedel ◽  
Thomas Wilke
Keyword(s):  
Type Species ◽  
Sister Group ◽  
Molecular Data ◽  
Character Evolution ◽  
Phylogenetic Position ◽  
Sister Group Relationship ◽  
Data Sets ◽  
Sequencing Data ◽  
The Family ◽  
Anatomical Characters

The phylogenetic position of the subfamily Pyrgulinae within the superfamily Rissooidea has been discussed very controversially. Different data sets not only led to different evolutionary scenarios but also to different systematic classifications of the taxon. The present study uses detailed anatomical data for two pyrgulinid taxa, the type species of the subfamily, Pyrgula annulata (Linnaeus, 1767), and the type species of the little known genus Dianella, D. thiesseana (Kobelt, 1878), as well as DNA sequencing data of three gene fragments from representatives of eight rissooidean families to A) infer the phylogenetic position of Pyrgulinae with emphasis on its relationships within the family Hydrobiidae, B) to study the degree of concordance between anatomyand DNAbased phylogenies and C) to trace the evolution of anatomical characters along a multi-gene molecular phylogeny to find the anatomical characters that might be informative for future cladistic analyses. Both anatomical and molecular data sets indicate either a very close or even sister-group relationship of Pyrgulinae and Hydrobiinae. However, there are major conflicts between the two data sets on and above the family level. Notably, Hydrobiidae is not monophyletic in the anatomical analysis. The reconstruction of anatomical character evolution indicates that many of the characters on which the European hydrobioid taxonomy is primarily based upon are problematic. The inability to clearly separate some hydrobiids from other distinct families based on those characters might explain why until only a few years ago, "Hydrobiidae" was a collecting box for numerous rissooidean taxa (mostly species with shells small and lacking any characteristic features). The present study not only stresses the need for comprehensive molecular studies of rissooidean taxa, it also demonstrates that much of the problems surrounding anatomical analyses in rissooidean taxa are due to the lack of comprehensive data for many representatives. In order to aid future comparativeanatomical studies and a better understanding of character evolution in the species-rich family Hydrobiidae, detailed anatomical descriptions for P. annulata and D. thiesseana are provided.Key words: Pyrgulinae, Pyrgula, Dianella, Hydrobiidae, phylogeny, DNA, anatomy, Greece

Fossil pollen from early Palaeogene sediments in western India provides phylogenetic insights into divergence history and pollen character evolution in the pantropical family Ebenaceae

2021 ◽  
Author(s):  
Mahi Bansal ◽  
Shivaprakash K Nagaraju ◽  
Ashish Kumar Mishra ◽  
Jeyakumar Selvaraj ◽  
Rajeev Patnaik ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Character Evolution ◽  
Fossil Pollen ◽  
Western India ◽  
Geological Time ◽  
Posterior Density ◽  
Origin And Evolution ◽  
Pollen Characters ◽  
The Family ◽  
Highest Posterior Density

Abstract Many plant families lack substantive fossil records, limiting our understanding of their origin and evolution. The abundance and preservation potential of pollen through geological time have helped to overcome such limitations and have provided reliable fossils for reconstructing biogeographical history and character evolution in many angiosperm families. Here, using scanning electron microscopy, we identified six Ebenaceae-type fossil pollen grains from early Palaeogene sediments of western India. Phenetic and phylogenetic analyses using pollen characters of fossil and extant taxa reavealed affinities of these fossils to three genera of Ebenaceae (Euclea, Royena and Diospyros). Furthermore, our divergence dating analysis using these fossils as priors suggested a Gondwanan origin for the family during the mid-Cretaceous [c. 107 Mya, 95% highest posterior density (HPD): 100–112 Mya] and supports the boreotropical and ‘out of India’ dispersal hypotheses as the most probable explanations for the present global distribution of the family. The study also supports the dispersal of the family into India, from Africa, through the Kohistan–Ladakh Arc during the Palaeocene. Finally, comparative phylogenetic analyses suggest significant synapomorphic and phylogenetic signals for a few selected pollen characters in Ebenaceae. Our findings have important implications for understanding the biogeography and evolution of the highly diverse and ecologically and economically important family Ebenaceae.

Phylogenetic Patterns in Menispermaceae Based on Multiple Chloroplast Sequence Data

2009 ◽  
Vol 34 (1) ◽  
pp. 44-56 ◽  
Author(s):  
Sara B. Hoot ◽  
Herbert Zautke ◽  
David J. Harris ◽  
Peter R. Crane ◽  
Susana S. Neves
Keyword(s):  
Bayesian Inference ◽  
Missing Data ◽  
Maximum Likelihood ◽  
Northern Hemisphere ◽  
Maximum Parsimony ◽  
Sequence Data ◽  
Character Evolution ◽  
The Family ◽  
Branch Support

Menispermaceae, a dioecious, largely pantropical family of vines and lianas, consists of approximately 70 genera. In this paper, we present phylogenies (derived using maximum parsimony, maximum likelihood, and Bayesian inference) based on chloroplast atpB and rbcL sequence data for 42 Menispermaceae genera (60 species) and 15 outgroup genera representing all families in the Ranunculales. Results of this work confirm that a clade consisting of Berberidaceae and Ranunculaceae is sister to the Menispermaceae and that Menispermaceae is highly supported as monophyletic. Within Menispermaceae, Menispermum and Sinomenium, two genera with distributions in the Northern Hemisphere, are weakly to moderately supported as sister to all remaining Menispermaceae. Many of the tribes as described by previous workers are not monophyletic. To expand both the data and sampling, we combined our atpB and rbcL data with previously published ndhF data for two additional analyses: 1) for matching species and 2) for all genera available, including those with either atpB/rbcL or ndhF missing (22% missing data). All trees produced from our three analyses were highly congruent, especially where branch support was high. Four major clades were recovered from all analyses and are informally named. Superimposing our geographical distributions on our atpB/rbcL phylogeny indicates that many well supported clades have distributions on multiple continents, probably due to both vicariance and dispersal. Several previous hypotheses regarding trends in character evolution are tested; our phylogenies suggest that the following are all derived character states within the family: arborescent habit; acrodromous, peltate, compound, or lobed leaves; absence of condyle and endosperm; smooth endosperm; fused stamens; and tricolpate pollen.

Triassic sponges (Sphinctozoa) from Hells Canyon, Oregon

1988 ◽  
Vol 62 (03) ◽  
pp. 419-423 ◽  
Author(s):  
Baba Senowbari-Daryan ◽  
George D. Stanley
Keyword(s):  
Endemic Species ◽  
Upper Triassic ◽  
Island Arc ◽  
Tropical Island ◽  
The Family ◽  
Wallowa Terrane ◽  
Unique Condition ◽  
Hells Canyon

Two Upper Triassic sphinctozoan sponges of the family Sebargasiidae were recovered from silicified residues collected in Hells Canyon, Oregon. These sponges areAmblysiphonellacf.A. steinmanni(Haas), known from the Tethys region, andColospongia whalenin. sp., an endemic species. The latter sponge was placed in the superfamily Porata by Seilacher (1962). The presence of well-preserved cribrate plates in this sponge, in addition to pores of the chamber walls, is a unique condition never before reported in any porate sphinctozoans. Aporate counterparts known primarily from the Triassic Alps have similar cribrate plates but lack the pores in the chamber walls. The sponges from Hells Canyon are associated with abundant bivalves and corals of marked Tethyan affinities and come from a displaced terrane known as the Wallowa Terrane. It was a tropical island arc, suspected to have paleogeographic relationships with Wrangellia; however, these sponges have not yet been found in any other Cordilleran terrane.

Electron Microscopy of Mycoplasma Pneumoniae

1971 ◽  
Vol 29 ◽  
pp. 258-259 ◽  
Author(s):  
E. S. Boatman ◽  
G. E. Kenny
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Growth Phase ◽  
Hela Cells ◽  
Sulfonic Acid ◽  
Gamma Globulin ◽  
Horse Serum ◽  
Morphological Aspects ◽  
The Family

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.

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