Tandem fusion, centric fusion, and chromosomal evolution in the cotton rats, genus Sigmodon

1980 ◽  
Vol 26 (2-4) ◽  
pp. 199-210 ◽  
Author(s):  
F.F.B. Elder
Keyword(s):  
Centric Fusion ◽  
Chromosomal Evolution ◽  
Tandem Fusion ◽  
Cotton Rats

Karyotypes and meiosis of the Australian Tettigoniidae (Orthoptera) II. The genus Nanodectes Rentz (Tettigoniinae)*

1991 ◽  
Vol 5 (1) ◽  
pp. 33 ◽  
Author(s):  
N Ueshuma ◽  
DCF Rentz
Keyword(s):  
Chromosome Number ◽  
X Chromosome ◽  
Chromosome Evolution ◽  
Centric Fusion ◽  
Chromosome Rearrangements ◽  
Karyotypic Evolution ◽  
Telocentric Chromosome ◽  
Species Ranges ◽  
Tandem Fusion ◽  
Different Populations

The karyotypes and meioses from males of the species in the shield-backed katydid genus Nanodectes Rentz (Tettigoniinae) have been studied. The chromosome number of these species ranges from 2n = 15 to 2n =23 in the male. The male karyotypes were all X – 0 and the X was always the largest telocentric chromosome. Four types of chromosome systems are found in different populations of N. triodiae Rentz: 2n = 15 (6 metacentric + 8 telocentric autosomes + X), 2n = 15 (4 metacentric + 10 telocentric autosomes + X), 2n = 17 (4 metacentric+ 12 telocentric autosomes + X) and 2n = 19 (2 metacentric + 16 telocentric autosomes + X). Chromosome rearrangements, such as centric fusion and tandem fusion, appear to have played an important role in chromosome evolution at the inter- and intra-specific levels in Nanodectes. Possible pathways of karyotypic evolution and speciation are discussed.* Part I: pp. 303-51 in: 'The Tettigoniidae: Biology, Ecology, Systematics'. Eds W. J. Bailey and D. C. F. Rentz. (Crawford House: Bathurst.)

Monophyleticism and Polyphyleticism in the Gekkonidae - a Chromosomal Perspective

1987 ◽  
Vol 35 (6) ◽  
pp. 641 ◽  
Author(s):  
M King
Keyword(s):  
Pericentric Inversion ◽  
Centric Fusion ◽  
Chromosomal Evolution ◽  
Heterogeneous Group ◽  
Ancestral Karyotype ◽  
Chromosomal Data ◽  
Group Comparisons

Kluge (1967, 1983) proposed that the four subfamilies within the Gekkonidae were monophyletic assemblages, but that the Gekkoninae could be divided into two tribes on the basis of hyoid apparatus structure. Whilst agreeing that four subfamilies were present in the Gekkonidae, Moffatt (1973) argued that those groups of non-Eublepharine gekkos which remained after the differentiation of the Diplo- dactylinae and Sphaerodactylinae, and which had not become sufficiently distinct to be classified into separate subfamilies, had been lumped together as the Gekkoninae. Subsequently, Russell (1976, 1979) found that at least seven distinct groups could be defined within the Gekkoninae on the basis of toe structure. In the present paper I compare chromosomal evolution in the monophyletic Diplodactylinae and that in the possibly polyphyletic Gekkoninae, to test whether the tribal subdivision made by Kluge (1983) is valid, or whether this is a far more heterogeneous group as Russell and Moffatt proposed. The chromosomal data from 47 of the 92 species show that the Diplodactylinae have evolved from a 2n = 38 all acrocentric ancestral karyotype by the processes of pericentric inversion and centric fusion. In contrast, an analysis of 74 species from the Gekkoninae shows that eight distinct putative ancestral karyomorphs are present, 2n=32, 34, 36, 38, 40, 42, 44 and 46, each of which is acrocentric or telocentric. Numerous fusions, inversions, additions and tandem fusions have occurred within each of these categories. These data suggest that the Gekkoninae are a polyphyletic assemblage, and group comparisons indicate that there is some agreement with the morphogroups proposed by Russell (1976).

scholarly journals Microsatellite and Chromosome Evolution of Parthenogenetic Sitobion Aphids in Australia

Genetics ◽  
1996 ◽  
Vol 144 (2) ◽  
pp. 747-756 ◽  
Author(s):  
Paul Sunnucks ◽  
Phillip R England ◽  
Andrea C Taylor ◽  
Dinah F Hales
Keyword(s):  
Sexual Reproduction ◽  
Chromosome Evolution ◽  
Genetic Recombination ◽  
Allelic Variation ◽  
Repeat Unit ◽  
Chromosomal Evolution ◽  
Microsatellite Variation ◽  
Wide Range ◽  
Sexual Recombination ◽  
Minimum Numbers

Abstract Single-locus microsatellite variation correlated perfectly with chromosome number in Sitobion miscanthi aphids. The microsatellites were highly heterozygous, with up to 10 alleles per locus in this species. Despite this considerable allelic variation, only seven different S. miscanthi genotypes were discovered in 555 individuals collected from a wide range of locations, hosts and sampling periods. Relatedness between genotypes suggests only two successful colonizations of Australia. There was no evidence for genetic recombination in 555 S. miscanthi so the occurrence of recent sexual reproduction must be near zero. Thus diversification is by mutation and chromosomal rearrangement alone. Since the aphids showed no sexual recombination, microsatellites can mutate without meiosis. Five of seven microsatellite differences were a single repeat unit, and one larger jump is likely. The minimum numbers of changes between karyotypes corresponded roughly one-to-one with microsatellite allele changes, which suggests very rapid chromosomal evolution. A chromosomal fission occurred in a cultured line, and a previously unknown chromosomal race was detected. All 121 diverse S. near fragariae were heterozygous but revealed only one genotype. This species too must have a low rate of sexual reproduction and few colonizations of Australia.

scholarly journals Resistance of Cotton Rats, Sigmodon hispidus, to Primary Infection by Nippostrongylus brasiliensis

2002 ◽  
Vol 64 (5) ◽  
pp. 423-426 ◽  
Author(s):  
Hendra WIBAWA ◽  
Deni NOVIANA ◽  
Kimiyuki TSUCHIYA ◽  
Fadjar SATRIJA ◽  
Yoichiro HORII
Keyword(s):  
Primary Infection ◽  
Nippostrongylus Brasiliensis ◽  
Sigmodon Hispidus ◽  
Cotton Rats

scholarly journals Chromosomal painting of the sandpiper (Actitis macularius) detects several fissions for the Scolopacidae family (Charadriiformes)

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Melquizedec Luiz Silva Pinheiro ◽  
Cleusa Yoshiko Nagamachi ◽  
Talita Fernanda Augusto Ribas ◽  
Cristovam Guerreiro Diniz ◽  
Patricia Caroline Mary O´Brien ◽  
...  
Keyword(s):  
Chromosome Painting ◽  
Diploid Number ◽  
Chromosomal Evolution ◽  
Long Distance ◽  
Chromosomal Painting ◽  
Cytogenetic Studies ◽  
Burhinus Oedicnemus ◽  
Clear Idea ◽  
First Time

Abstract Background The Scolopacidae family (Suborder Scolopaci, Charadriiformes) is composed of sandpipers and snipes; these birds are long-distance migrants that show great diversity in their behavior and habitat use. Cytogenetic studies in the Scolopacidae family show the highest diploid numbers for order Charadriiformes. This work analyzes for the first time the karyotype of Actitis macularius by classic cytogenetics and chromosome painting. Results The species has a diploid number of 92, composed mostly of telocentric pairs. This high 2n is greater than the proposed 80 for the avian ancestral putative karyotype (a common feature among Scolopaci), suggesting that fission rearrangements have formed smaller macrochromosomes and microchromosomes. Fluorescence in situ hybridization using Burhinus oedicnemus whole chromosome probes confirmed the fissions in pairs 1, 2, 3, 4 and 6 of macrochromosomes. Conclusion Comparative analysis with other species of Charadriiformes studied by chromosome painting together with the molecular phylogenies for the order allowed us to raise hypotheses about the chromosomal evolution in suborder Scolopaci. From this, we can establish a clear idea of how chromosomal evolution occurred in this suborder.

scholarly journals Invasive Burmese pythons alter host use and virus infection in the vector of a zoonotic virus

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Nathan D. Burkett-Cadena ◽  
Erik M. Blosser ◽  
Anne A. Loggins ◽  
Monica C. Valente ◽  
Maureen T. Long ◽  
...  
Keyword(s):  
Biological Diversity ◽  
Dilution Effect ◽  
Transmission Risk ◽  
Infection Prevalence ◽  
Host Use ◽  
Invasive Predator ◽  
Cotton Rats ◽  
Generalized Linear Mixed Effects ◽  
Python Bivittatus ◽  
Southern Florida

AbstractThe composition of wildlife communities can have strong effects on transmission of zoonotic vector-borne pathogens, with more diverse communities often supporting lower infection prevalence in vectors (dilution effect). The introduced Burmese python, Python bivittatus, is eliminating large and medium-sized mammals throughout southern Florida, USA, impacting local communities and the ecology of zoonotic pathogens. We investigated invasive predator-mediated impacts on ecology of Everglades virus (EVEV), a zoonotic pathogen endemic to Florida that circulates in mosquito-rodent cycle. Using binomial generalized linear mixed effects models of field data at areas of high and low python densities, we show that increasing diversity of dilution host (non-rodent mammals) is associated with decreasing blood meals on amplifying hosts (cotton rats), and that increasing cotton rat host use is associated with increasing EVEV infection in vector mosquitoes. The Burmese python has caused a dramatic decrease in mammal diversity in southern Florida, which has shifted vector host use towards EVEV amplifying hosts (rodents), resulting in an indirect increase in EVEV infection prevalence in vector mosquitoes, putatively elevating human transmission risk. Our results indicate that an invasive predator can impact wildlife communities in ways that indirectly affect human health, highlighting the need for conserving biological diversity and natural communities.

Systemic Immunoprophylaxis of Nasal Respiratory Syncytial Virus Infection in Cotton Rats

1995 ◽  
Vol 171 (2) ◽  
pp. 440-443 ◽  
Author(s):  
I. R. Sami ◽  
F. M. Piazza ◽  
S. A. Johnson ◽  
M. E. R. Darnell ◽  
M. G. Ottolini ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Virus Infection ◽  
Respiratory Syncytial Virus Infection ◽  
Cotton Rats ◽  
Syncytial Virus
Sign in / Sign up

Export Citation Format

Share Document