François Joseph Lapointe

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A matrix of delta T mode values for 10 birds, including 9 nonpasserines and a suboscine passerine flycatcher, was generated by DNA-DNA hybridization. Within the most derived lineages, all bootstrapped and jackknifed FITCH trees lend strong support to sister-groupings of the two swift families, of hummingbirds to swifts, and of these to a clade containing(More)
Resolution of the total evidence (i.e., character congruence) versus consensus (i.e., taxonomic congruence) debate has been impeded by (1) a failure to employ validation methods consistently across both tree-building and consensus analyses, (2) the incomparability of methods for constructing as opposed to those for combining trees, and (3) indifference to(More)
For more than 10 years, systematists have been debating the superiority of character or taxonomic congruence in phylogenetic analysis. In this paper, we demonstrate that the competing approaches can converge to the same solution when a consensus method that accounts for branch lengths is selected. Thus, we propose to use both methods in combination, as a(More)
The jackknife strict consensus has been used to detect topological incompatibilities in phylogenetic trees derived from distance data. We here extend this approach to account for branch lengths, as well as topological relationships, when comparing jackknife pseudoreplicates. The average consensus procedure is used to derive a tree reflecting the agreement(More)
As part of a large-scale study on brain morphometrics and adaptations in mammals, we addressed the problem of chiropteran evolution. A specific statistical framework was designed to test which of two competing hypotheses (bat monophyly vs. diphyly) is more strongly supported by quantitative brain data. Our analyses, based on 120 species, revealed that(More)
A method is presented to test the relationship between a phylogenetic tree derived from brain morphology, and different hypotheses describing the evolution of a behavioral trait. This is a question of interest for evolutionary psychologists and behavioral biologists. The paper first discusses how hypotheses for behavioral evolution should be coded for such(More)
In this paper, we evaluate the relative performance of competing approaches for estimating phylogenies from incomplete distance matrices. The direct approach proceeds with phylogenetic reconstruction while ignoring missing cells, whereas the indirect approach proceeds by estimating the missing distances prior to phylogenetic analysis. Two distinct indirect(More)
Double-walled carbon nanotubes (DWNTs) present an original coaxial geometry in which the inner wall is naturally protected from the environment by the outer wall. Covalent functionalization is introduced here as an effective approach to investigate DWNT devices. Performed using an aryldiazonium salt, the functionalization is reversible upon thermal(More)
This work revisits the physics giving rise to the carbon nanotube phonon bands in the midinfrared. Our measurements of doped and undoped samples of single-walled carbon nanotubes in Fourier transform infrared spectroscopy show that the phonon bands exhibit an asymmetric line shape and that their effective cross section is enhanced upon doping. We relate(More)
Quantitative description of reaction mechanisms in aqueous phase electrochemistry requires experimental characterization of local water structure at the electrode/aqueous interface and its evolution with changing potential. Gaining such insight experimentally under electrochemical conditions is a formidable task. The potential-dependent structure of a(More)