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Posts tagged ‘phylogenetics’

Thoughts: Bio-ontologies with only minimal predetermined relations

Time for some reflection on this (2015) Spring’s Weekly Discussion on Phenotype ontologies – origins, theory, applications, prospects, and challenges. It gets to be a little (and intentionally) provocative (as opposed to very carefully thought out) towards the end.

We started off three months ago with Daduhl et al. 2010, who provide an inspiring vision on the subject (page 370):

“The application of ontologies to systematics has the potential to force clarification and improve communication about morphological character diversity across taxonomic domains. As a result, ontologies could extend the applicability and level of universality of characters for phylogenetic analysis and improve the knowledge of evolutionary transformations. These computable vocabularies could enable efficient computer processing of vast amounts of data and allow the exploration and aggregation of data across studies that is currently difficult to do in morphology-based phylogenetics.”

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Presentations and posters at ECN and ESA 2014

Our lab has had an eventful joint ECN/ESA 2014 meeting and presentation/poster schedule of activities. Most presentations are now posted. Great meetings – even won recognition for our Twitter contributions.

ECN 2014

Symposium – Harvesting the fruits of our labor: Utilizing collections databases to advance 21st century entomology.

1. Neil Cobb, Katja Seltmann & Nico Franz. 2014. The current state of arthropod biodiversity data: Addressing impacts of global change. Presentation.

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Taxonomic concept identification, reconciliation, and the Open Tree of Life – Part 1

“Part 1” – allowing for subsequent parts (e.g., for the blue/non-blue use case; now added at end of post). The relevant OpenTree background discussion is here:

There as several interesting and generally closely overlapping issues and views here. I will pick just (or mainly) the one introduced by Jonathan Rees (November 02, 2014).

“Here’s another example I’m struggling with: there are currently a couple of species in OTT that are misclassified as crustaceans instead of molluscs. When we fix this problem, there will be an incompatible ‘change’ in the membership of Arthropoda. Does this mean that the new group should get a new identifier? – after all its identity in some sense has changed. If so, annotations and OTU mappings linked to the old id have no home in the tree. It doesn’t get a new id with the current taxonomy generator, which assumes that names are tied uniquely to taxon concepts (with some exceptions), but with a more principled system where groups are defined by membership or phylogenetic hypotheses, it might. This would have an impact on OTU mappings and annotation carryover. I don’t have a good answer to this one, but am working on ways to anchor the semantics of ids.”

I am attempting to reproduce this under varying scenarios in the Euler/X toolkit. Starting simple, then expanding. I have created an initial scenario with two phylogenetic perspectives of the Ecdysozoa (molting animals) sec. ott1 (= OpenTree Topology at time =1; the later version) versus Ecdysozoa sec. ott0 (OTT at time = 0; the earlier version. Initially, an alignment with complete taxonomic congruence.

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BIGCB Workshop at UC Berkeley: Tackling the Taxon Concept Problem

November 7-9, 2014. Coolest workshop theme, like, ever. Organized by Brent Mishler and Staci Markos of the UC Berkeley Jepson Herbarium.

Understanding Taxon Ranges in Space and Time: Tackling the Taxon Concept Problem

A Workshop Sponsored by the Berkeley Initiative in Global Change Biology

Friday, November 7, 2014, 1002 VLSB, open to all who are interested.

1:00 pm: Brent Mishler  –  Introduction to the themes and goals of this workshop.

1:10 pm: Edward Gilbert  –  Ideas for incorporating taxonomic concepts into Symbiota.

1:40 pm: Robert Guralnick  –  Map of Life and the challenge of heterogeneous names data for determining species ranges.

2:10 pm: Gaurav Vaidya  –  Tracking taxonomic changes: how, where and why, with examples from the Avibase database of taxon concepts. Link & PDF

2:40 pm: Coffee Break.

3:00 pm: Robert Peet  –  Taxon concepts as essential infrastructure for large-scale data integration: lessons from VegBank, SEEK and BIEN. PDF

3:30 pm: Nico Franz  –  Tracking taxonomic change across classifications and phylogenies. PDF

4:00 pm: Alan Weakley  –  Applying concept maps to 7100 vascular plants of the Southeastern United States, and some thoughts on ‘atomic concepts’ and their utility at the specimen level.  PDF

4:30 pm: Nico Cellinese  –  Thoughts on the right approach to query trees based on phyloreferences (ontologized phylogenetic definitions).

Additional Workshop Notes

  • Communicated by Robert Peet  –  Taxonomic concept infrastructure-related entities requiring identifiers. PDF

Weekly reading: Intermittent evolution and robustness of phylogenetic models

Models of evolution used in phylogenetic reconstruction make specific assumptions which (in their entirety, and globally applied) are ultimately wrong. They are also approximately right. What does this even mean? This week’s reading gets us into the notion of robustness of phylogenetic models to violations of their inherent assumptions. An important piece of the “which method should I use?” puzzle. Let’s see if we can identify other pieces too.

Nguyen, M.A.T., T. Gesell & A. von Haeseler. 2012. ImOSM: Intermittent evolution and robustness of phylogenetic methods. Molecular Biology and Evolution 29: 663-673. Available on-line here.

Weekly reading: Lemmon & Lemmon on high-throughput genomic data for phylogenetics

Time to direct our Weekly Discussion series towards Next-Generation Sequencing (NGS) – theory and methods. First up is:

Lemmon, E.M. & A.R. Lemmon. 2013. High-throughput genomic data in systematics and phylogenetics. Annual Review of Ecology, Evolution, and Systematics 44: 99–121. Available on-line here.

Weekly reading: Philosophy of statistical phylogenetic methods

After a long summer hiatus, our Weekly Discussion series resumes for the Fall semester of 2014 (this time also as a one-credit under-/graduate seminar course “Current Topics in Systematics”). On the menu this semester we have the theory and practice of Next Generation Sequencing, but the corresponding papers will  have to wait a few weeks to make room for 2-3 unrelated topics on which new, intriguing papers have come out over the summer.

The first of these is on the philosophical correlates of statistical phylogenetic inference!

Barker, D. 2014. Seeing the wood for the trees: philosophical aspects of classical, Bayesian and likelihood approaches in statistical inference and some implications for phylogenetic analysis. Biology & Philosophy 29. (21 pp.). Available on-line here.

Weekly reading: Next-generation sequencing platforms

…and now onto something completely different; or maybe not? We have completed the Spring 2014 circle of papers on characters, coding, homology, and philosophical implications. Here is the list again for review:

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