both groups spin very similar orb webs. When juxtaposed to the morphological disparity be-tween the spiders themselves, the similanty in the form of cheir webs and in the manner in which they are constructed has inspired a classic evolutionary controversy•the single versus the dual origin of the orb

thousands of other papers at

We describe a new species of Cettia from the Crown Prince Range, Bougainville Island, North Solomons Province, Papua New Guinea. By combining morphometric and molecular phylogenetic techniques, we attempt to broaden our understanding of evolutionary processes within the genus Cettia in the southwest Pacific. The new species proves to be distinct with respect to several morphological characteristics that are most probably related to a more terrestrial lifestyle than that of its congeners. Molecular data agree with morphological data in establishing that these birds are at least as distinct from the other island forms of Cettia as those forms are from each other, far exceeding intraspecific variation. These data and the restricted distribution of the population on Bougainville strongly support recognition of a new species. The application of molecular phylogenetic techniques also supports the idea that the new species and other island forms of Cettia confined to mountains on southwest Pacific islands are derived from a single common ancestor rather than being independently derived from one or more mainland forms. In addition, the relatively recent discovery of two new species of Cettia suggests that additional forms await discovery in other poorly known areas of the southwest Pacific. Our results point to the need for further molecular studies and for additional field research into the distribution and ecology of forest songbirds on islands.

The monophyletic origin of freshwater cray sh

is not monophylet-ic (3) on methodological grounds, including use of a suboptimal substitution matrix, lack of correction for among-site rate variation (ASRV), and biased taxon selection. They fur-ther introduce a method (5) that recodes nucle-otide sequences into only two categories— purines (R) and pyrimidines (Y

pancrustaceans. A Bayesian statistical (non-clock) estimate of divergence times suggests a Precambrian origin for Pancrustacea (600 Myr ago or more), which precedes the first unambiguous arthropod fossils by over 60 Myr.

Hydroporinae): reinforcement of the hypothesis of monophyletic origin and discussion of phenotypic accommodation to a hypogaeic environment

) is also in contact with the anterior tentorium. Phylogenetic analysis of cephalic data results in monophyletic Zygentoma including T. gertschi. Zygentoma are supported by the presence of a set of labial muscles originating at the postocciput, presence of an additional intralabral muscle, and four labial

doi:10.1111/j.1365-2052.2008.01848.x Monophyletic origin of domestic bactrian camel (Camelus bactrianus) and its evolutionary relationship with the extant wild camel (Camelus bactrianus ferus)

. The phylogeny of I clade showed strong support for the monophyletic origin of such group of elements in scorpions. Three separate lineages can be distingiushed in the phylogenetic tree of CR1 clade. The large fraction of the isolated elements ap-peared to be defective.