Karyotypic data and the specific status and taxonomic affinites of Rattus villosissimus and R. sordidus

1975 ◽  
Vol 23 (2) ◽  
pp. 293 ◽  
Author(s):  
PR Baverstock ◽  
CHS Watts ◽  
JT Hogarth
Keyword(s):  
Chromosomal Rearrangements ◽  
Separate Species

Although R. villosissimus and R. sordidus have been considered to be conspecific, they differ karyotypically in at least 11 chromosomal rearrangements. It seems likely that they diverged early in the evolution of Rattus, and they should be regarded as separate species.

Chromosomal rearrangements in rock wallabies, Petrogale (Marsupialia: Macropodidae). II. G-banding analysis of Petrogale godmani

Genome ◽  
1989 ◽  
Vol 32 (6) ◽  
pp. 935-940 ◽  
Author(s):  
M. D. B. Eldridge ◽  
P. G. Johnston ◽  
R. L. Close ◽  
P. S. Lowry
Keyword(s):  
Chromosomal Rearrangements ◽  
Centric Fusion ◽  
Common Ancestry ◽  
Chromosome 4 ◽  
Chromosome 5 ◽  
Separate Species ◽  
Submetacentric Chromosome ◽  
Ancestral Chromosome ◽  
Banding Analysis ◽  
Cape York

Chromosomal rearrangements in the two currently recognised races of Petrogale godmani were examined using C- and G-banding. The nominate race P. godmani godmani (2n = 20) was found to possess an inverted chromosome 5 and an acrocentric 6–10 fusion, which can be derived from a 6–10 centric fusion by a centromeric transposition. The Cape York race (2n = 22) was found to retain the ancestral submetacentric chromosome 4 and the ancestral chromosome 5. Thus despite their genie similarity, the two races clearly have major chromosomal differences and should be regarded as separate species. Petrogale g. godmani shares two derived chromosomes with another Queensland taxon, the assimilis race of P. assimilis, indicating recent common ancestry. The Cape York race retains characteristics of an ancestral stock of Petrogale and its genic similarity with P. g. godmani could therefore be the result of extensive introgression.Key words: chromosomal rearrangements, G-banding, Marsupialia, Petrogale.

Karyotypic Differences Between Two Species of Pomatoceros, P. Triqueter and P. Lamarckii (Polychaeta: Serpulidae)

1998 ◽  
Vol 78 (4) ◽  
pp. 1113-1126 ◽  
Author(s):  
D.R. Dixon ◽  
P.L. Pascoe ◽  
L.R.J. Dixon
Keyword(s):  
Chromosomal Rearrangements ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Species Variation ◽  
Species Status ◽  
Separate Species ◽  
Polychaete Species ◽  
Species Integrity ◽  
South West England

Consistent with most other closely-related polychaete species which have been analysed cytogenetically to-date, Pomatoceros triqueter and P. lamarckii share an identical chromosome number (2n=24) and have a number of other karyotypic features in common. However, commensurate with their separate species status, their karyotypes differ at least in four chromosome positions as a result of structural chromosomal rearrangements. With a rDNA probe using the FISH technique, we have been able to demonstrate that the nucleolar organizer region (NOR) occurs at the same site on the same pair of chromosomes in the two species, which indicates that an inversion event is unlikely to have been the cause of the species variation in this particular case. Taken together, these karyotypic differences may be indicative of a chromosomal barrier to the formation of fertile offspring; an important feature for maintaining species integrity where the two forms occur sympatrically, such as in parts of south-west England.

Electron Microscopy and image analysis of nucleo-protein complexes

1994 ◽  
Vol 52 ◽  
pp. 88-89
Author(s):  
E. H. Egelman ◽  
X. Yu
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Normal Cell ◽  
Genetic Recombination ◽  
Protein Complexes ◽  
Chromosomal Rearrangements ◽  
Reca Protein ◽  
E Coli ◽  
Helical Polymer ◽  
Specific Protease

The RecA protein of E. coli has been shown to mediate genetic recombination, regulate its own synthesis, control the expression of other genes, act as a specific protease, form a helical polymer and have an ATPase activity, among other observed properties. The unusual filament formed by the RecA protein on DNA has not previously been shown to exist outside of bacteria. Within this filament, the 36 Å pitch of B-form DNA is extended to about 95 Å, the pitch of the RecA helix. We have now establishedthat similar nucleo-protein complexes are formed by bacteriophage and yeast proteins, and availableevidence suggests that this structure is universal across all of biology, including humans. Thus, understanding the function of the RecA protein will reveal basic mechanisms, in existence inall organisms, that are at the foundation of general genetic recombination and repair.Recombination at this moment is assuming an importance far greater than just pure biology. The association between chromosomal rearrangements and neoplasms has become stronger and stronger, and these rearrangements are most likely products of the recombinatory apparatus of the normal cell. Further, damage to DNA appears to be a major cause of cancer.

Willughby's Buzzard: names and misnomers of the European Honey-buzzard (Pernis apivorus)

2018 ◽  
Vol 45 (1) ◽  
pp. 80-91 ◽  
Author(s):  
T. R. Birkhead ◽  
I. Charmantier ◽  
P. J. Smith ◽  
R. Montgomerie
Keyword(s):  
Accurate Description ◽  
Separate Species ◽  
Common Buzzard ◽  
Buteo Buteo ◽  
John Ray ◽  
The Common ◽  
Francis Willughby

The European Honey-buzzard (Pernis apivorus) was first accurately described and clearly distinguished from the Common Buzzard (Buteo buteo) by Francis Willughby and John Ray in their Ornithology, originally published in Latin in 1676. Alfred Newton's statement that Pierre Belon had described the species over a century earlier is not entirely correct, as Belon confused this honey-buzzard's features with those of the common buzzard and even appeared uncertain whether it was a separate species. One of Willughby's important contributions to ornithology was the identification and use of “characteristic marks” to distinguish and identify species, including those that distinguish the European Honey-buzzard from the Common Buzzard. Because Willughby provided the first accurate description of Pernis apivorus  – and because his contribution to ornithology has never been formally recognized –  we propose that the common name of the European Honey-buzzard be changed to Willughby's Buzzard.

An importance of soil humidification in forming of avifauna of arboreal plantation in the Biosphere reserve «Askania Nova» (un-reproductive period)

2016 ◽  
Vol 27 (3-4) ◽  
pp. 55-69
Author(s):  
M. A. Listopadsky
Keyword(s):  
Soil Moisture ◽  
Influence Factors ◽  
Data Communication ◽  
Biosphere Reserve ◽  
Reproductive Period ◽  
Defined Contribution ◽  
Separate Species ◽  
Steppe Birds ◽  
Reserve Forest ◽  
Autumn And Winter

With gradient analysis investigated the role of soil moisture in the formation of the modern population of birds in the reserve forest plantations. Soil moisture was divided into seven grades. For this purpose used grass cover and the coefficient of local moistening. His proposed PhD L. P. Travleev. This method allows knowing the degree of influence of soil moisture at the birds. We analyzed birds species composition, population, placement in space and power of influence factors (soil moisture). Investigations were carried out on the territory of the Biosphere Reserve «Askania Nova». We studied the birds which live in the reserve at the end of the summer, autumn and winter. This happened from 2006 to 2013 years. Specially was studied as permanently specific form of birds is found in a particular humidity. The degree of coupling was studied using the amount of information that transmits to the local bird humidification. For 68 species of birds are the options of the population density, coefficient koligatsii and data communication with the seven variants of soil moisture. For all kinds of set information «price» of each option dampening that contributes to the formation of a particular community of birds. Thus, the defined contribution to the formation of soil moisture forest bird communities. Species representation and density gradient within the test moisture is not in direct linear relationship from moisture and ranges from 11 (very coldly) to 50 species (moist soil). The density of the community varies from 0,5 birds / hectare (very dry) to 269 birds / hectare (fresh soil). The strongest link between the information and the formation of moisture gradient structure avifauna is typical in a fresh soil – bird on the edge, and wet – forest representatives. These types of humidification function is performed starting in the formation of two major blocks dendrophilous community. The steppe birds give way to forest representatives when the soil slightly moist. The main conclusion of our study includes the following: than wetter the soil the more species of birds lives in the forest; some graduation humidity are the most important for separate species of birds; it is very important for birds, there are places where one can drink water. Further invasive alien species can occur where the soil is moist. Forest with dry soil is already fully occupied by birds.

The experience of holding the cycles of assisted reproductive technology with defrost, a biopsy, genetic study and refreezing of embryos in patients with multiple unsuccessful implantations

2016 ◽  
pp. 166-170
Author(s):  
Y.V. Masliy ◽  
◽  
I.O. Sudoma ◽  
P.S. Mazur ◽  
D.A. Mykytenko ◽  
...  
Keyword(s):  
Chromosomal Rearrangements ◽  
Genetic Diagnosis ◽  
Morphological Characteristics ◽  
Implantation Rate ◽  
Ovarian Response ◽  
Reproductive Technologies ◽  
Comparative Genome Hybridization ◽  
Comparative Genome ◽  
Vitro Fertilization

The objective: to study the possibility of using frozen blastocysts for biopsy and genetic testing and performance measurement transfer euploeded 5–7-day-old embryos after thawing, biopsies, refreezing and thawing in patients with unsuccessful implantation. Patients and methods. The object of the study was the group of patients with repeated failure of implantation (4) in programs of auxiliary reproductive technologies (ART), subject to transfer to the uterus in total (i.e. in all the programs) for at least 6 good quality embryos based on morphological characteristics). All women had sufficient ovarian reserve. The patient was treated for infertility within the ART programs of the clinic of reproductive medicine "Nadiya" in the period from 2006 to 2016. The sample included couples who were not carriers of chromosomal rearrangements, without anomalies of the uterus (congenital and acquired: a doubling of the uterus, one-horned uterus, intrauterine membrane, synechia, submucous myoma of the uterus). All women had a positive ovarian response to controlled stimulation with gonadotropins (at least 7 oocytes) and a sufficient number of cryopreserved embryos. The first group (G1) included 64 women who trophectodermal a biopsy was performed on fresh blastocysts (in a loop controlled ovarian hyperstimulation). The second group (G2) were included 31 women who underwent thawing previously cryopreserved blastocysts trophectodermal re-biopsy and vitrification of blastocysts. Results. It was found that the performance of transfers euploid embryos that were vitrified, bioptrone and revitriphted, a little lower than those that were bioptrone fresh and vitrified only once. At the same time computationa genetic diagnosis previously vitrified blastocysts using comparative genome hybridization in patients with recurrent failed implantation allows to obtain a reasonable pregnancy rate (58%), implantation rate (33.3 %) and the birth of living children (45.1 %). Conclusion. Reprising biopropane embryos does not cause significant destructive impact and allows you to achieve pregnancy and birth of the alive child. Key words: in vitro fertilization, reusable unsuccessful implantation, a method of comparative genome hybridization, refreezing.

Analysis of the differences between Syntormon pallipes and S. pseudospicatus (Diptera: Dolichopodidae): morphological and molecular data

2019 ◽  
Vol 28 (2) ◽  
pp. 305-316
Author(s):  
M.A. Chursina ◽  
I.Ya. Grichanov
Keyword(s):  
Dna Analysis ◽  
Distinct Species ◽  
Molecular Data ◽  
Wing Shape ◽  
Morphological Data ◽  
12S Rrna ◽  
Separate Species ◽  
Geometric Morphometric ◽  
Geometric Morphometric Analysis ◽  
Morphological And Molecular Data

The recent catalogues of the family Dolichopodidae considered Syntormon pallipes (Fabricius, 1794) and S. pseudospicatus Strobl, 1899 as separate species. In this study, we used three approaches to estimate the significance of differences between the two species: molecular analysis (COI and 12S rRNA sequences), analysis of leg colour characters and geometric morphometric analysis of wing shape. The morphological data confirmed the absence of significant differences between S. pallipes and S. pseudospicatus found in the DNA analysis. Significant differences in the wing shape of two species have not been revealed. Hence, according to our data, there is no reason to consider S. pseudospicatus as a distinct species.

Curly Birch: A Variety or a Separate Species?

2020 ◽  
pp. 26-48
Author(s):  
L. V. Vetchinnikova ◽  
◽  
A. F. Titov ◽  
◽  
Keyword(s):  
Separate Species
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