1 / 18

Chapter 25: Phylogeny & Systematics

Chapter 25: Phylogeny & Systematics. The Science of grouping and classifying organisms. Phylogeny. Is the evolutionary history of a species or groups of species Species is a group of individuals who are capable of reproducing fertile/viable offspring.

tamar
Download Presentation

Chapter 25: Phylogeny & Systematics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 25: Phylogeny & Systematics The Science of grouping and classifying organisms

  2. Phylogeny • Is the evolutionary history of a species or groups of species • Species is a group of individuals who are capable of reproducing fertile/viable offspring.

  3. Systematics is an analytical approach to understanding the diversity and relationships of organisms alive today and extinct • Phylogeniesare based on common ancestors both past and present from fossil records, morphological similarities and molecular evidence What is this related to today? Fossil evidence

  4. Morphological Similarities • Homologous structures (same structure, different function) show common ancestry and divergent evolution • Analogous structures (same function, different structure) show convergent evolution

  5. Molecular Homologies • Using genes, proteins (proteomics) and DNA to show evolutionary relationships • Molecular homologies also can be seen at the level of the finished protein product encoded by the DNA, as shown in this comparison of amino acid sequence in hemoglobin (146 amino acids in length) of different species:

  6. With so many organisms alive and extinct, there is a need to organize all living things • Taxonomyis the ordered division of organisms into categories based on a set of characteristics used to assess similarities and difference.

  7. Carolus Linnaeus (1748) • Biography • Came up with a taxonomic system based on morphology and not evolutionary trends • Designed the modern system of classification dividing organisms into 7 taxa and giving each species its universal scientific name. Today we use 8 taxa • Binomial nomenclature – Genus and species names • Homo sapiens, Pantherapardus

  8. Classification Class – Mammalia Phylum – Chordata Kingdom – Animalia Domain - Eukarya

  9. Taxonomic orderHere’s your song Taxon Us Domain Eukarya Kingdom Animalia Phylum Chordata Class Mammalia Order Primate Family HominidaeGenus Homo species sapiens

  10. Phylogenetic Tree shows branching relationships between organisms and their evolutionary relationships

  11. Cladograms • Phylogenetic systematics with shared characteristics • Shows common ancestry • Clades – a group of species that include an ancestral species and all of its descendants

  12. Shared primitive characteristics would be like having a backbone, being unicellular, or symmetry

  13. Shared derived characteristics would be like hair which shows a more recent characteristics and uniqueness to the clade

  14. OutgroupsvsIngroups

  15. Ingroup Derived Characteristics Cladogram

  16. Construct a cladogram Placenta Hair Limbs Jaws Segmented Multicellular

More Related