Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
CHAPTER 10 Taxonomy and Phylogeny of Animals 10-1 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-2 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Linnaeus and Taxonomy More than 1.5 million species of animals are named Estimated that these account for Taxonomy (aka - Systematics) 10-3 Less than 20% of all animals currently alive Less than 1% of extinct animals Formal system for naming and classifying species Science of classifying organisms based on similarity, biogeography, molecular components, development, etc. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Linnaeus and Taxonomy Greek philosopher Aristotle first classified organisms (350 BC) Carolus Linnaeus designed the current system of classification (1750) Swedish botanist with experience classifying flowers Used morphology (study of form and structure) to develop a classification system of animals and plants Divided animal kingdom into species and gave each a distinctive name 10-4 Grouped species into genera, genera into orders, and orders into classes His classification scheme has been drastically altered, but the basic principle is still followed Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Carolus Linnaeus 10-5 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Linnaeus and Taxonomy Hierarchy of taxonomic ranks now includes 7 major groups Kingdom, phylum, class, order, family, genus, and species Now, the new level of Domain is also used. All animals are placed in Kingdom Animalia, or Domain Eukarya Taxa (Taxon) - Groups of animals that share a particular set of characteristics. Example: True Flies “Diptera” - single pair of wings Each rank can be subdivided into additional levels of taxa 10-6 Superclass, suborder, etc. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-7 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Division of Life - Milestones Linnaeus 1735 2 ki ngdoms (not treated) Haeckel 1866 [5] 3 ki ngdoms Protista Chatton 1937 [6] 2 em pires Copela nd 1956 [7] 4 ki ngdoms Whittaker 1969 [2] 5 ki ngdoms Proka ryota Mone ra Mone ra Animalia Plantae Animalia Euka ryota Woese e t al. 1990 [8] 3 domai ns Eubacte ria Bacte ria Archaea Protista Archaebacte ria Protista Fung i Fung i Plantae Plantae Plantae Animalia Animalia Animalia Protista Vegetab ilia Woese et al. 1977 [3] 6 ki ngdoms Euka rya Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 3 Domains - current proposal Based on ribosomal RNA sequences Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Taxonomy Nomenclature: assignment of a distinctive name to each species A scientific name of an animal consists of two words (binomial nomenclature) First word is the genus and is capitalized Second is the species written in lower case Scientific name should be printed in italics or underlined if handwritten 10-10 Homo sapiens Homo sapiens Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Taxonomy Some animals are subspecies, usually caused by Geographic locations. They are referred to as trinomials (3 names) 10-11 All three terms are in italics Subspecies is also in lower case Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ensantina eschscholtzii (salamander) has many subspecies. E.e. plantens, E.e. picta, E.e.croceater Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Taxonomic Characters and Phylogenetic Reconstruction Cladogram Diagram illustrating hierarchy of clades (groups of animals with common ancestry) Outgroups used Phylogenetic tree (compared to cladogram) Additional information concerning: ancestors, duration of lineages, amount of evolutionary change (some mathematical calculation and numerical values usually invovled) 10-13 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. A cladogram Amphioxus is the “outgroup” because it doesn’t share any of the defining characteristic with the other taxa. What characteristic separates Bass from Horses? 10-14 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Taxonomic Characters and Phylogenetic Reconstruction Sources of Phylogenetic Information (What do we use to identify animals in a Phylogenetic Tree??) Comparative Morphology Examines shapes, sizes and development of organisms Skull bones, limb bones, scales, hair and feathers Living specimens and fossils are used 10-15 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Taxonomic Characters and Phylogenetic Reconstruction Comparative Biochemistry Analyzes sequences of amino acids in proteins and nucleotides sequences in nucleic acids Comparative biochemistry can be applied to fossils Comparative Cytology Examines variation in number, shape and size of chromosomes Used almost exclusively on living specimens 10-16 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Phylogenetic Tree based On Cytology: Comparing base substitutions on Cyctochrome C (a respiratory protein). #’ s represent number of Mutations that occurred at the ancestral division. 10-17 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Animal Kingdom Patterns of Organization Characteristics used to Classify: Symmetry Asymmetrical (no central body point/axis) ex. sponge Bilateral (if divided right/left sides are mirror image) ex. vertebrates Radial (any plane cut through organism makes mirror image) ex. Sea anemone Embryonic Tissue Layers: Diploblastic - 2 tissues (ectoderm and endoderm) Triploblastic - 3 tissue layers (also mesoderm) Zygote Cleavage Protostome - blastopore becomes mouth Deuterostome blastopore becomes anus Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Major Subdivisions of the Animal Kingdom Traditional groupings based on embryological and anatomical characters Branch (Parazoa): phylum Porifera, the sponges and phylum Placozoa Branch (Eumetazoa): all other phyla 10-20 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Major Subdivisions of the Animal Kingdom Branch Eumetazoa Grade I (Radiata): phyla Cnidaria Grade II (Bilateria): all other phyla Division A (Protostomia): Mouth is first opening Subdivision of Protostomes by coelom formation: Acoelomates: phyla Platyhelminthes, Pseudocoelomates: phyla Nematoda, Eucoelomates: phyla Mollusca, Annelida, Arthropoda Division B (Deuterostomia): 10-21 Anus is first opening phyla Echinodermata, Chordata