Les FlyLadies, on fait l'ménage!! On s'organise!!!!

Ce forum a été créé le 1er mai/08....Il est encore en construction mais vous pouvez déja commencer à vous inscrire.A très vite mes "futurs" collègues "maniaques" du ménage..

Vous n'êtes pas identifié.

#1 18-01-2020 03:24:55

Iris Forster
Nouveau membre
Date d'inscription: 18-01-2020
Messages: 0

puma fenty

Our objectives were to refine the puma fenty phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent.

Interestingly, Barnett et al. (2005) provided molecular evidence indicating that the extinct North American felid Miracinonyx trumani is the puma's closest relative, with a divergence time estimated at 3.19 MYA. This finding would support the hypothesis of a North American origin for the puma, with subsequent colonization of South America by this species, in parallel with that of the jaguarundi.In a thorough study of puma phylogeography, Culver et al. (2000) assessed puma women shoes the current and historical genetic diversity present in this species, based on a large sampling of individuals from across its range.

In the present study we employ this longer ND5 segment to investigate the evolutionary history of P. concolor , with emphasis on South American populations, which were previously found to harbor puma shoes in canada high levels of diversity and inferred to have played a key role in the historical demography of this species ( Culver et al. , 2000 ). Given that the geographic sampling of South American pumas was limited in that first study, we aimed here to expand the representation of the various regions of this sub-continent, so as to allow refined inferences of population structure, maternal gene flow and demographic history.

To select a marker that would provide suitable information levels, we initially examined the mtDNA fragments used in previous studies, especially those involving Neotropical felids ( e.g. Eizirik et al. , 1998 puma shoes women , 2001 ; Johnson et al. , 1998 , 1999 ; Culver et al. , 2000 ). We selected the ca. 750 bp-long fragment of the ND5 gene reported by Trigo et al. (2008) , thus considerably increasing the information content derived from this marker relative to the previous phylogeographic study of the puma ( Culver et al. , 2000 ). Finally, the availability of ND5 sequences for the extinct felid Miracinonyx trumani ( Barnett et al. , 2005 ) was an additional asset of this segment, allowing the inclusion of this fossil taxon in some analyses.

AMOVAs were performed using ¦ st computed from a pairwise matrix based on p -distances. Statistical significance of ¦ st values was tested using 10,000 permutations. To minimize the effect of prior assumptions on puma geographic subdivision we tested a variety of different scenarios attempting to identify the best possible way to represent historical population structure in this species ( i.e. the one that maximizes the estimated ¦ st ). These AMOVAs were based on two sample sets: (1) South America (SA) only: and (2) the full sample of SA, Central America (CA) and North America (NA).

Finally, we conducted a set of analyses to investigate the demographic history of pumas. We performed puma shoes for basketball neutrality tests (Tajima's D, Fu & Li' D* and F*, Fu's Fs) with DnaSP, as well as a mismatch distribution analysis ( Rogers and Harpending, 1992 ; Schneider and Excoffier, 1999 ) with Arlequin. In addition, we used the program Beast 1.6.1 ( Drummond and Rambaut, 2007 ) to perform estimates of coalescence times and past demography. We defined the best model of nucleotide substitution for our data set, which was the HKY ( Hasegawa et al. , 1985 ) G model, using the Akaike Information Criterion (AIC, Akaike, 1974 [img]http://www.fteacadia.ca/images/shoes/puma shoes for basketball-117ydl.jpg[/img] ) implemented in jModelTest 0.1 ( Posada, 2008 ).

Hors ligne

 

Pied de page des forums

Créez Votre Propre Forum
Insérer vos Graphiques
Dictionnaires de Traduction
Hébergé par ForumCrea.com