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Fu's Fs (fu + f)
Selected AbstractsLimited phylogeographic structure in the flightless ground beetle, Calathus ruficollis, in southern CaliforniaDIVERSITY AND DISTRIBUTIONS, Issue 5 2007Stylianos Chatzimanolis ABSTRACT The California Floristic Province is home to more than 8000 species of beetles, yet their geographical patterns of supra- and infraspecific diversity remain largely unexplored. In this paper, we investigate the phylogeography and population demographics of a flightless ground beetle, Calathus ruficollis (Coleoptera: Carabidae), in southern California. We sampled 136 specimens from 25 localities divided into 10 populations using a fragment of the mitochondrial cytochrome oxidase I gene. We tested several hypotheses, including the association of geography with particular clades and populations, the degree of differentiation among regions, and the expansion of populations. Parsimony and Bayesian phylogenetic analyses along with nested clade analysis and amova indicate a deep split between the southern Sierra Nevada population and populations south and west. This split corresponds closely to the split between subspecies C. ruficollis ignicollis (southern Sierra Nevada) and C. ruficollis ruficollis. Populations otherwise exhibit limited geographical structure, though Fst values indicate some local differentiation. Mismatch distributions and Fu's Fs indicate range expansion of several populations, suggesting that some structure may have been obscured by recent exchange. The population of C. ruficollis on Santa Cruz Island, which might have been expected to be isolated, shares several haplotypes with mainland populations, appearing to represent multiple colonizations. [source] Implications of mitochondrial DNA polyphyly in two ecologically undifferentiated but morphologically distinct migratory birds, the masked and white-browed woodswallows Artamus spp. of inland AustraliaJOURNAL OF AVIAN BIOLOGY, Issue 6 2006Leo Joseph The white-browed woodswallow Artamus superciliosus and masked woodswallow A. personatus (Passeriformes: Artamidae) are members of Australia's diverse arid- and semi-arid zone avifauna. Widely sympatric and among Australia's relatively few obligate long-distance temperate-tropical migrants, the two are well differentiated morphologically but not ecologically and vocally. They are pair breeders unlike other Artamus species, which are at least facultative cooperative breeders. For these reasons they are an excellent case in which to use molecular data in integrative study of their evolution from ecological and biogeographical perspectives. We used mitochondrial DNA (mtDNA) to test whether they are each other's closest relatives, whether they evolved migration independently, whether they have molecular signatures of population expansions like some other Australian arid zone birds, and to estimate the timing of any inferred population expansions. Their mtDNAs are monophyletic with respect to other species of Artamus but polyphyletic with respect to each other. The two species appear not to have evolved migration independently of each other but their morphological and mtDNA evolution have been strongly decoupled. Some level of hybridization and introgression cannot be dismissed outright as being involved in their mtDNA polyphyly but incomplete sorting of their most recent common ancestor's mtDNA is a simpler explanation consistent with their ecology. Bayesian phylogenetic inference and analyses of diversity within the two species (n=77) with conventional diversity statistics, statistical parsimony, and tests for population expansion vs stability (Tajima's D, Fu's Fs and Ramos-Onsin and Rozas's R2) all favour recent population increases. However, a non-starlike network suggests expansion(s) relatively early in the Pleistocene. Repeated population bottlenecks corresponding with multiple peaks of Pleistocene aridity could explain our findings, which add a new dimension to accruing data on the effects of Pleistocene aridity on the Australian biota. [source] Independent evolution of migration on the South American landscape in a long-distance temperate-tropical migratory bird, Swainson's flycatcher (Myiarchus swainsoni)JOURNAL OF BIOGEOGRAPHY, Issue 6 2003Leo Joseph Abstract Aim, To understand the evolution of long-distance temperate,tropical migration in a South American bird, Swainson's flycatcher (Myiarchus swainsoni). Methods, A total of 842 base pairs of the mitochondrial DNA genes ATPase 8 and 6 were sequenced from forty-nine individuals of the M. swainsoni complex from most of its range. Analyses measured the phylogenetic signal in the data, and tools of population genetics, phylogeography and phylogeny were used to interpret the evolution of the bird and its migration on the South American landscape. Results, Migratory populations in the M. swainsoni complex are not each other's closest relatives. The migratory subspecies M. s. swainsoni, which breeds in south-eastern South America, is not closely related to the rest of the complex. The remaining migratory populations of the subspecies M. s. ferocior and two intergrade populations are extremely closely related to non-migratory populations with which they form a well-supported clade despite substantial morphological differentiation from each other. Within this clade of migrants and non-migrants, net divergence across 4000 km of lowland South America is zero and most diversity is distributed among individuals not populations. Mismatch analyses and significant values of Tajima's D and Fu's Fs suggest the clade has undergone a very recent range expansion. Migration and the shifts of breeding distribution that accompanied its evolution evolved twice within what has recently been considered the polytypic species M. swainsoni. Furthermore, these shifts of range probably occurred at very different times as parts of different southward ,pulses' of humid, Amazonian taxa. Main conclusions, Evolution of temperate-tropical migration in the M. swainsoni complex has been spatio-temporally layered on the South American landscape. The analysis cautions that the historical biogeography underlying a single present-day migration system need not have been driven by a single set of environmental factors operating at one time. We suggest directions for further study of ecology and demography in zones of apparent contact between various migratory and non-migratory populations. [source] Population genetic studies of Alouatta belzebul from the Amazonian and Atlantic ForestsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2008F.F. Nascimento Abstract Cytochrome b DNA sequence data (ca. 1,140,bp) of 66 Alouatta belzebul from the Amazonian and the Atlantic Forests of Brazil were used for phylogenetic reconstructions and population studies. Our sample consisted of 60 specimens from the Amazonian Forest (captured in 1984 and 1998 in Pará-PA state) and six specimens from the Atlantic Forest (Paraíba-PB state). We found 32 haplotypes, 23 in PA-1984 (with 12 present in more than one individual), 11 in PA-1998 (with two present in more than one individual), and a single haplotype in the PB sample. Animals from PA-1984 and PA-1998 shared three haplotypes while animals from Pará and Paraíba did not share any haplotype. We found 57 variable sites, consisting of 53 transitions and four transversions, with most replacements occurring at third codon position (77.19%) and less frequently at first and second positions (10.53 and 12.28%, respectively). Genetic distance between all haplotypes varied between 0 and 1.2%. Nucleotide diversity estimates between PA-1984 haplotypes and PA-1998 haplotypes were the same (,=0.01), and haplotype diversity estimates were very similar (h=0.96 and 0.93 for PA-1984 and PA-1998, respectively). Maximum parsimony, median-joining, split decomposition, and TCS showed that PA and PB haplotypes had not drastically diverged and that subsequent radiation within these regions was not apparent. No temporal structure was found between PA-1984 and PA-1998. The sum of square deviation estimate for PA-1984 equaled 0.01 (P=0.23), in agreement with a hypothetical model of sudden expansion contrary to PA-1998 whose sum of square deviation estimate (0.40; P=0.04) was not compatible with this model, although the small sample size of PA-1998 as well as the smaller area of capture could have also accounted for this result. Fu's Fs and R2 statistical neutrality tests corroborated these propositions. Lack of drastic differentiation was attributable to the once existing connection between the Atlantic and the Amazonian forests at a non-distant past. Am. J. Primatol. 70:423,431, 2008. © 2007 Wiley-Liss, Inc. [source] | ||||||||||