The Future of Systematics: Tree-Thinking Without the Tree

Phylogenetic trees are meant to represent the genealogical history of life and apparently derive their justification from the existence of the tree of life and the fact that evolutionary processes are tree-like. However, there are a number of problems for these assumptions. Here it is argued that once we understand the important role that phylogenetic trees play as models which contain idealizations, we can accept these criticisms and deny the reality of the tree while justifying the continued use of trees in phylogenetic theory and preserving nearly all of what defenders of trees have called “the importance of tree-thinking.

Liberal ethnicity: beyond liberal nationalism and minority rights

This article tries to make the case for a variant of the good life based on a synthesis of liberalism and ethnicity. Liberal communitarianism's treatment of ethnicity tends to fall under the categories of either liberal culturalism or liberal nationalism. Both, it is argued, fail to come to terms with the reality of ethnic community, preferring instead to define ethnicity in an unrealistic, cosmopolitan manner. By contrast, this essay squarely confronts four practices that are central to ethnic communities: symbolic boundary-maintenance; exclusive and inflexible mythomoteurs ; the use of ancestry and race as boundary markers; and the desire among national groups to maintain their ethnic character. This article argues that none of these practices need contravene the tenets of liberalism as long as they are reconstructed so as to minimize entry criteria and decouple national ethnicity from the state. The notion of liberal ethnicity thereby constitutes an important synthesis of liberal and communitarian ends

Browsing Isolated Population Data

BACKGROUND: In our studies of genetically isolated populations in a remote mountain area in the center of Sardinia (Italy), we found that 80–85% of the inhabitants of each village belong to a single huge pedigree with families strictly connected to each other through hundreds of loops. Moreover, intermarriages between villages join pedigrees of different villages through links that make family trees even more complicated. Unfortunately, none of the commonly used pedigree drawing tools are able to draw the complete pedigree, whereas it is commonly accepted that the visual representation of families is very important as it helps researchers in identifying clusters of inherited traits and genotypes. We had a representation issue that compels researchers to work with subsets extracted from the overall genealogy, causing a serious loss of information on familiar relationships. To visually explore such complex pedigrees, we developed PedNavigator, a browser for genealogical databases properly suited for genetic studies. RESULTS: The PedNavigator is useful for genealogical research due to its capacity to represent family relations between persons and to make a visual verification of the links during family history reconstruction. As for genetic studies, it is helpful to follow propagation of a specific set of genetic markers (haplotype), or to select people for linkage analysis, showing relations between various branch of a family tree of affected subjects. AVAILABILITY: PedNavigator is an application integrated into a Framework designed to handle data for human genetic studies based on the Oracle platform. To allow the use of PedNavigator also to people not owning the same required informatics infrastructure or systems, we developed PedNavigator Lite with mainly the same features of the integrated one, based on MySQL database server. This version is free for academic users, and it is available for download from our sit

On Chinese and Western Family Trees: Mechanism and Performance

Family tree is an efficient data structure to store the kinship information in a family. There are basically two kinds of trees: Western Family Tree (WFT) and Oriental Family Tree such as Chinese Family Tree (CFT). To get an insight of their efficiency in the context of family kinship presentation and information extraction, in this paper we develop WFT and CFT presentation models and search algorithms, comparing their search performance and inherent mechanism. The study reveals that the computational cost is higher in CFT model, but it provides a greater gain in information retrieval and produces more details of the kinship between individuals in the family