Morphometric Relationship, Phylogenetic Correlation, and Character Evolution in the Species-Rich Genus Aphis (Hemiptera: Aphididae)

The species-rich genus Aphis consists of more than 500 species, many of them host-specific on a wide range of plants, yet very similar in general appearance due to convergence toward particular morphological types. Most species have been historically clustered into four main phenotypic groups (gossypii, craccivora, fabae, and spiraecola groups). To confirm the morphological hypotheses between these groups and to examine the characteristics that determine them, multivariate morphometric analyses were performed using 28 characters measured/counted from 40 species. To infer whether the morphological relationships are correlated with the genetic relationships, we compared the morphometric dataset with a phylogeny reconstructed from the combined dataset of three mtDNA and one nuclear DNA regions.Based on a comparison of morphological and molecular datasets, we confirmed morphological reduction or regression in the gossypii group unlike in related groups. Most morphological characteristics of the gossypii group were less variable than for the other groups. Due to these, the gossypii group could be morphologically well separated from the craccivora, fabae, and spiraecola groups. In addition, the correlation of the rates of evolution between morphological and DNA datasets was highly significant in their diversification.The morphological separation between the gossypii group and the other species-groups are congruent with their phylogenetic relationships. Analysis of trait evolution revealed that the morphological traits found to be significant based on the morphometric analyses were confidently correlated with the phylogeny. The dominant patterns of trait evolution resulting in increased rates of short branches and temporally later evolution are likely suitable for the modality of Aphis speciation because they have adapted species-specifically, rapidly, and more recently on many different host plants

Calculus using Mathematica: scientific projects and mathematical background

Calculus Using Mathematic

Calculus using Mathematica

Calculus Using Mathematic

Foundations of infinitesimal stochastic analysis

This book gives a complete and elementary account of fundamental results on hyperfinite measures and their application to stochastic processes, including the *-finite Stieltjes sum approximation of martingale integrals. Many detailed examples, not found in the literature, are included. It begins with a brief chapter on tools from logic and infinitesimal (or non-standard) analysis so that the material is accessible to beginning graduate students

Creative model-based diagrammatic cognition: The discovery of the “imaginary” non-euclidean geometry

The present article is devoted to illustrate the issue of the model-based and extra-theoretical dimension of cognition from the perspective of the famous discovery of non-Euclidean geometries. This case study is particularly appropriate because it shows relevant aspects – creative – of diagrammatic cognition, which involve intertwined processes of both explanatory and non-explanatory abduction. These processes act at the model-based level taking advantage of what I call mirror and unveiling diagrams. A description of important abductive heuristics is also provided: expansion of scope strategy, Euclidean/non-Euclidean model matching strategy, consistency-searching strategy