Presentation on theme: "Lecture 1 – Introduction and Importance of Systematics"— Presentation transcript:
1Lecture 1 – Introduction and Importance of Systematics Mayr - “the theory and practice of classifying organisms”.a-Taxonomy – includes species descriptions, taxonomic keys, and diagnoses.b-Taxonomy – includes identification of natural groups and biological classes.g-Taxonomy – includes study of evolutionary processes and patterns.BiosystematicsSociety of Systematic Biologists“The study of organismal diversity, including both the pattern of that diversityand the processes that have generated it.”
2only described 1.5 million (maybe around ~ 30 %) of them. II. Roles of Systematics.A. Provide a-taxonomy.57% of the 150 most prescribed drugs contain active ingredients derivedfrom natural compoundsThere may be ~5 million extant species on Earth (Costello et al. 2013), and we’veonly described 1.5 million (maybe around ~ 30 %) of them.B. Provide specimen identificationIndirectly, via keys.Directly, via expert examination.
3II. Roles of Systematics. C. Maintain CollectionsProvide reference for identifications.Serve as permanent repository for important specimens.Type specimensVoucher specimensPhysical evidence of range shifts
4II. Roles of Systematics. D. ClassificationProvide a framework of names that is universal.This must reflect evolutionary history – monophyletic groupsIt also must be stable (we should resist change).Do we want taxonomic ranks to be equilibrated across groups?
5II. Roles of Systematics. E. Phylogeny estimation.ISI Web of Science “phylogen*” >643,500 papers published since 2004Understanding AdaptationStudy of Evolutionary Patterns and ProcessesCo-speciation – for example between parasites and their hosts.Historical Biogeography – molecular phylogeographyHybridizationGene Duplication and Genome StructureDeep-time evolutionary Patternsextinction and speciation rates (e.g., lineages-through time)species selection and the study of evolutionary trends
6Inferred a single donor infected II. Roles of Systematics.Molecular EpidemiologyHIV transmission inEdinburghInferred a single donor infectedthe blood supply.
7II. Roles of Systematics. Molecular Epidemiology – Ebola Virus: Spread from central Africa or new variant?“The current outbreak is likely caused by a Zaire ebola virus lineage that has spread from Central Africa into Guinea and West Africa in recent decades, and does not represent the emergence of a divergent and endemic virus.”
8II. Roles of Systematics. ForensicsLouisiana v. Richard J. SchmidtRichard Schmidt, M.D.Janice TrahanSchmidt was accused of intentionally injecting Trahan with HIV hecollected from his HIV+ patients.This allegation predicts that HIV collected from Trahan should be veryclosely related to HIV collected from one or more of his patients.
9Epidemiology & Forensics Why Study Phylogenies?Epidemiology & ForensicsTrahan’s HIVThis (along with other evidence) lead to Schmidt’s conviction.