Biology subjects

Franz, N.

Publications and source records attributed to Franz, N..

3 recordsLinked to original sources

bioRxiv2017

Verbalizing phylogenomic conflict: Representation of node congruence across competing reconstructions of the neoavian explosion

Phylogenomic research is accelerating the publication of landmark studies that aim to resolve deep divergences of major organismal groups. Meanwhile, systems for identifying and integrating the novel products of phylogenomic inference - such as newly supported clade concepts - have not kept pace. However, the ability to verbalize both node concept congruence and conflict across multiple, (in effect) simultaneously endorsed phylogenomic hypotheses, is a critical prerequisite for building synthetic data environments for biological systematics, thereby also benefitting other domains impacted by these (conflicting) inferences. Here we develop a novel solution to the conflict verbalization challenge, based on a logic representation and reasoning approach that utilizes the language of Region Connection Calculus (RCC-5) to produce consistent alignments of node concepts endorsed by incongruent phylogenomic studies. The approach employs clade concept labels to individuate concepts used by each source, even if these carry identical names. Indirect RCC-5 modeling of intensional (property-based) node concept definitions, facilitated by the local relaxation of coverage constraints, allows parent concepts to attain congruence in spite of their differentially sampled children. To demonstrate the feasibility of this approach, we align two recently published phylogenomic reconstructions of higher-level avian groups that entail strong conflict in the \"neoavian explosion\" region. According to our representations, this conflict is constituted by 26 instances of input \"whole concept\" overlap. These instances are further resolvable in the output labeling schemes and visualizations as \"split concepts\", thereby providing the provenance services needed to build truly synthetic phylogenomic data environments. Because the RCC-5 alignments fundamentally reflect the trained, logic-enabled judgments of systematic experts, future designs for such environments need to promote a culture where experts routinely assess the intensionalities of node concepts published by our peers - even and especially when we are not in agreement with each other.

evolutionary biology↗

bioRxiv2017

Endosymbiont diversity and evolution across the weevil tree of life

As early as the time of Paul Buchner, a pioneer of endosymbionts research, it was shown that weevils host diverse bacterial endosymbionts, probably only second to the hemipteran insects. To date, there is no taxonomically broad survey of endosymbionts in weevils, which preclude any systematic understanding of the diversity and evolution of endosymbionts in this large group of insects, which comprise nearly 7% of described diversity of all insects. We gathered the largest known taxonomic sample of weevils representing four families and 17 subfamilies to perform a study of weevil endosymbionts. We found that the diversity of endosymbionts is exceedingly high, with as many as 44 distinct kinds of endosymbionts detected. We recovered an ancient origin of association of Nardonella with weevils, dating back to 124 MYA. We found repeated losses of this endosymbionts, but also cophylogeny with weevils. We also investigated patterns of coexistence and coexclusion.

evolutionary biology↗

bioRxiv2017

To increase trust, change the social design behind aggregated biodiversity data

Growing concerns about the quality of aggregated biodiversity data are lowering trust in large-scale data networks. Aggregators frequently respond to quality concerns by recommending that biologists work with original data providers to correct errors \"at the source\". We show that this strategy falls systematically short of a full diagnosis of the underlying causes of distrust. In particular, trust in an aggregator is not just a feature of the data signal quality provided by the sources to the aggregator, but also a consequence of the social design of the aggregation process and the resulting power balance between individual data contributors and aggregators. The latter have created an accountability gap by downplaying the authorship and significance of the taxonomic hierarchies - frequently called \"backbones\" - they generate, and which are in effect novel classification theories that operate at the core of data-structuring process. The Darwin Core standard for sharing occurrence records plays an under-appreciated role in maintaining the accountability gap, because this standard lacks the syntactic structure needed to preserve the taxonomic coherence of data packages submitted for aggregation, potentially leading to inferences that no individual source would support. Since high-quality data packages can mirror competing and conflicting classifications, i.e., unsettled systematic research, this plurality must be accommodated in the design of biodiversity data integration. Looking forward, a key directive is to develop new technical pathways and social incentives for experts to contribute directly to the validation of taxonomically coherent data packages as part of a greater, trustworthy aggregation process.

evolutionary biology↗