Search results for "phylogenetic"

Application of molecular markers to investigate genetic diversity in Sicilian livestock

2014

La diversità genetica delle specie e razze di interesse zootecnico, rappresenta un’importante risorsa in tutti i sistemi di allevamento . Per lo studio della diversità genetica, nel corso dei decenni sono stati sviluppati diversi metodi che si basano su informazioni del pedigree o su dati molecolari (microsatelliti e SNPs, Single Nucleotide Polymorphisms). Con l’aumento della disponibilità di marcatori molecolari per la maggior parte delle specie di interesse zootecnico, e con lo sviluppo di sofisticate tecniche analitiche, sta crescendo la capacità di caratterizzare la variabilità genetica delle razze. Inoltre, ad oggi, poche sono le informazioni sulla diversità genetica delle razze e dell…

Taxonomic and phylogenetic relations of Allium chamaespathum Boiss., a remarkable species of Balkan Flora

2018

Allium chamaespathum Boiss., the only autumn-flowering species of Sect. Allium, was studied based on morphology, karyology, seed coat microsculpturing and DNA sequences from several populations.

Phylogenetic analysis of the Sicilian Hieracium taxa (Asteraceae) using "DNA barcoding": preliminary data

2014

Museum primatological collections: a valuable source of ancient DNA

2008

Analysis of early strains of the norovirus pandemic variant GII.4 Sydney 2012 identifies mutations in adaptive sites of the capsid protein.

2014

AbstractGlobal surveillance for norovirus identified in 2012 the emergence of a novel pandemic GII.4 variant, termed Sydney 2012. In Italy, the novel pandemic variant was identified as early as November 2011 but became predominant only in the winter season 2012–2013. Upon sequencing and comparison with strains of global origin, the early Sydney 2012 strains were found to differ from those spreading in 2012–2013 in the capsid (ORF2) putative epitopes B, C and D, segregating into a distinct phylogenetic clade. At least three residues (333, 340 and 393, in epitopes B, C and D, respectively) of the VP1 varied among Sydney 2012 strains of different clades. These findings suggest that the spread …

Epidemiological dynamics of norovirus GII.4 variant New Orleans 2009.

2015

Norovirus (NoV) is one of the major causes of diarrhoeal disease with epidemic, outbreak and sporadic patterns in humans of all ages worldwide. NoVs of genotype GII.4 cause nearly 80–90 % of all NoV infections in humans. Periodically, some GII.4 strains become predominant, generating major pandemic variants. Retrospective analysis of the GII.4 NoV strains detected in Italy between 2007 and 2013 indicated that the pandemic variant New Orleans 2009 emerged in Italy in the late 2009, became predominant in 2010–2011 and continued to circulate in a sporadic fashion until April 2013. Upon phylogenetic analysis based on the small diagnostic regions A and C, the late New Orleans 2009 NoVs circulati…

Much more than a clasp: Evolutionary pattern of amplexus diversity in anurans

2019

ABSTRACTThe evolution and diversification of animal reproductive modes have been pivotal questions in behavioral ecology. Amphibians present the highest diversity of reproductive modes among vertebrates, involving various behavioral, physiological and morphological traits. One of such features is the amplexus, the clasp or embrace of males on females during reproduction, which is almost universal to anurans. Hypotheses about the origin amplexus are limited and have not been thoroughly tested, nor had they taken into account evolutionary relationships in most comparative studies. However, these considerations are crucial to understand the evolution of reproductive modes. Here, using an evolu…

Evolutionary processes in the emergence and recent spread of the syphilis agent, Treponema pallidum

2022

Abstract The incidence of syphilis has risen worldwide in the last decade in spite of being an easily treated infection. The causative agent of this sexually transmitted disease is the bacterium Treponema pallidum subspecies pallidum (TPA), very closely related to subsp. pertenue (TPE) and endemicum (TEN), responsible for the human treponematoses yaws and bejel, respectively. Although much focus has been placed on the question of the spatial and temporary origins of TPA, the processes driving the evolution and epidemiological spread of TPA since its divergence from TPE and TEN are not well understood. Here, we investigate the effects of recombination and selection as forces of genetic diver…

Revision of New World Species of Shore Fly Genus <I>Discomyza</I> Meigen (Diptera: Ephydridae)

2005

Two species of Discomyza Meigen occur in the New World, one, D. u-signata Cresson, naturally and the other, D. maculipennis (Wiedemann), apparently as an introduction. These species are revised and their malacophagous breeding habits are documented. The species treatments include the first detailed descriptions and illustrations of structures from the male terminalia, lectotype designations for Notiphila maculipennis Wiedemann and its New World synonym (D. balioptera Loew), as well as phylogenetic and biogeographic information, including maps. Although congeners, these two species are apparently not closely related, and their occurrence in the New World is independent of each other. D. macu…

Ventastega curonica and the origin of tetrapod morphology.

2008

The gap in our understanding of the evolutionary transition from fish to tetrapod is beginning to close thanks to the discovery of new intermediate forms such as Tiktaalik roseae. Here we narrow it further by presenting the skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica from the Late Devonian of Latvia, a transitional intermediate form between the 'elpistostegids' Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega. Ventastega is the most primitive Devonian tetrapod represented by extensive remains, and casts light on a part of the phylogeny otherwise only represented by fragmentary ta…