LIFE 103 1st Edition Lecture 2 Outline of Last Lecture II Studying the Biology of Organisms III Patterns in Diversity IV Syllabus information a Teachers b Lab c Notes d Studying e Exams V Becoming a Scientist Outline of Current Lecture VI Organizing the Diversity of Life VII Taxonomy a Science of classifying things VIII Phylogenetic Trees IX Different Ways to Classify X Changes to Classification XI Horizontal Gene Transfer and its Complications a Movement of genes from one genome to another Current Lecture How Have Biologists Organized Life II Bins older III Trees newer How do you organize the diversity of life IV Carl Linnaeus 1707 to 1778 V Organized them into bins VI Create bins of similar organisms a Taxonomy is the science of classifying things b Hierarchical structure with big bins containing smaller bins VII Linnaeus s hierarchical classification kingdom phylum class order family genus species These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute VIII Bins at the highest taxonomic level are kingdoms IX The most similar are in the same species Binomial Classification X Any two animals of the same species can produce viable offspring XI The scientific name of each species is referred to by its genus and species name XII The use of a scientific name helps avoid confusion deer oak tree XIII Fig 26 3 slide 5 Goal of Taxonomy XIV An accurate taxonomy should reflect evolutionary relatedness XV Individuals within a bin should contain all the organisms that share a common ancestor a Wolves and coyotes are both in the family canidae b Their common ancestor had dog like characteristics XVI A phylogeny is a branching diagram that reflects the evolutionary history of a group of organisms XVII Fig 26 4 slide 7 Phylogenetic Trees XVIII Hypothesis about evolutionary relationships XIX Branches provide information being adjacent does not XX Data sources a Morphological characters physical features b Molecular characters DNA sequences XXI Correct answer to Fig 26 C XXII Correct answer to Fig 26 10 A monophyletic group a Paraphyletic group b Polyphyletic group An organism s evolutionary history is documented in its genome XXIII Comparing nucleic acids or other molecules to infer relatedness is a valuable tool for tracing organism s evolutionary history XXIV DNA that codes for rRNA changes slowly a Useful for history over hundreds of millions of years XXV mtDNA evolves rapidly a Used to explore recent evolutionary events XXVI Helps with divergence Biologists have NOT FINISHED organizing XXVII New species are still being discovered XXVIII New molecular DNA data is being gathered from known species XXIX New phylogenetic trees are being constructed XXX Although Linnaeus began studying the relationship among species the work is FAR from over XXXI Natural history is the scientific process of identifying patterns in nature Recent Major Revisions XXXII Before 1969 3 Kingdoms a Plants animals protists XXXIII 1969 to 1990 5 kingdoms a Plants animals fungi protists monera bacteria etc XXXIV 1990 3 domains a Eukarya b Archaea c Bacteria XXXV Fig 26 21 XXXVI More closely related to Archaea Eukarya than Bacteria XXXVII Fig 26 21 C closer look at Eukarya XXXVIII Protists organization was Polyphyletic before it was revised A Simple Tree of Life XXXIX The tree of life suggests that eukaryotes and archaea are more closely related to each other than to bacteria XL The tree of life is based largely on rRNA genes as these have evolved slowly Horizontal Gene Transfer XLI There have been substantial interchanges of genes between organisms in different domains XLII Horizontal gene transfer is the movement of genes from one genome to another XLIII Horizontal gene transfer complicates efforts to build a tree of life Endosymbiotic Theory XLIV Lynn Margulis 1977 proposed that mitochondria and chloroplasts in Eukaryotes came from symbiotic bacteria XLV Endo within symbionts living together XLVI Fig 26 22 Clicker questions Which two are closely related Eukarya and Archaea