lec5_taxo&phylo.pdf

9/12/24 ANIMAL TAXONOMY, PHYLOGENY & ORGANIZATION BIO 110 [email protected] 1 IMPORTANT TERMS ØTaxonomy vs Systematics ØPhylogeny vs Ontogeny ØCladogram vs Phylogenetic Tree 2...

9/12/24 ANIMAL TAXONOMY, PHYLOGENY & ORGANIZATION BIO 110 [email protected] 1 IMPORTANT TERMS ØTaxonomy vs Systematics ØPhylogeny vs Ontogeny ØCladogram vs Phylogenetic Tree 2 1  9/12/24 IMPORTANT TERMS ØSystematics the study of the kinds and diversity of organisms and the relationships among them ØTaxonomy the theory and practice of identifying, describing, naming, and classifying organisms 3 IMPORTANT TERMS ØOntogeny ØPhylogeny is a description of the evolutionary history of a group of organisms and usually depicted using tree diagrams “Taxonomy reflects phylogeny” 4 2  9/12/24 Evolutionary Groups A monophyletic group includes the last common ancestor (LCA) plus all the descendants of the LCA. A polyphyletic group includes A paraphyletic the descendants group includes the only and LCA but does not excludes the LCA include one or more descendants. 5 IMPORTANT TERMS ØCladogram Displays related characteristics ØPhylogenetic Tree Shows evolutionary and genetic distance 6 3  9/12/24 CLADOGRAM PHYLOGENETIC TREE Relationships are supported by Relationships are hypothetical molecular evidence 7 Sample Cladogram of Vertebrates (Miller and Tupper, 12e) 8 4  9/12/24 Sample Phylogenetic Tree 9 (a) A base sequence alignment for four species and an outgroup. (b) A phylogeny derived from the base sequences shown in (a). The notation 7: C → T is interpreted as a change in the base cytosine (C) to the base thymine (T) at character site 7 in the base sequence. Phylogeny from a Base Sequence Alignment (Miller and Tupper, 12e) 10 5  9/12/24 Basic Classification Hierarchy - DOMAIN - KINGDOM - PHYLUM (OR DIVISION) - CLASS - ORDER - FAMILY - GENUS - SPECIES (many levels can have sublevels: e.g. subfamily) 11 Basic Classification Hierarchy - DOMAIN (Eukarya) - KINGDOM (Animalia) - PHYLUM (Chordata) - SUBPHYLUM (Vertebrata) - CLASS (Mammalia) - ORDER (Primate) - FAMILY (Hominidae) - GENUS (Homo) - SPECIES (Homo sapiens) (many levels can have sublevels: e.g. subfamily) 12 6  9/12/24 Taxon / Taxa ØWhat is a TAXON (pl. taxa) ØNO ABSOLUTE way to determine if something should be a genus, a family or a phylum ØStill there is much agreement as to what goes in a group such as GREEN ALGAE or FLOWERING PLANTS or BACTERIA 13 The Species ØThe only taxon that has ‘biological reality’ ØHuman Beings (a species) ØWhat is our scientific name? ØSpecies: Homo sapiens Linnaeus ØGenus: Homo ØSpecific Epithet: sapiens ØGenus + Specific Epithet = Species ØAuthor Citation: Linnaeus 14 7  9/12/24 Classify / Classification ØGOAL: a natural classification ØA Classification: information storage and retrieval system ØWhat type of information to use? ØEverything and anything Ø (morphology, anatomy, distribution, cytology, genetics, DNA homologies, behaviors, etc.) 15 Nomenclature ØNaming things ØWhy a system of Nomenclature? ØWhy scientific names? Why not just use common names? ØBinomial System ØWhy latinized names? ØVery specific rules --- Why is this important? 16 8  9/12/24 Classification Hierarchy Revisited - ALL LIVING THINGS (= Storage Building) - DOMAIN (= a floor in the building) - KINGDOM (= large storage room) - DIVISION or PHYLUM (= file cabinet) - CLASS (= drawer) - ORDER (= large file folder) - FAMILY (= smaller folder in the large folder) - GENUS (= stapled packet) - SPECIES (= single page) 17 Changing (?) Classifications ØHow many Kingdoms? ØTwo Three Five Six Plantae Protista Monera Archaebacteria Animalia Plantae Protista Eubacteria Animalia Fungi Protista Plantae Fungi Animalia Plantae Animalia ØWhat is the difference? ØProtista also known as Protoctista 18 9  9/12/24 Changing (?) Classifications 19 ANIMAL ORGANIZATION: FEATURES Segmentation Cephalization Tissues & Coelom Organs Germ layers Pattern of early devmt Symmetry 23 10  9/12/24 Germ Layer Invertebrates are either diploblastic or triploblastic Copyright Pearson Prentice Hall 24 Coelom Invertebrates are either acoelomates, pseudocoelomates or coelomates The coelom allows for compartmentalization of the body parts, so that different organ systems can evolve and nutrient transport is possible. 25 11  9/12/24 Coelom in Triploblastic Animals Triploblastic animals have tissues derived from ectoderm, mesoderm, and endoderm. (a) Triploblastic acoelomate form. (b) Triploblastic pseudocoelomate form. Note the absence of mesodermal lining on the gut tract. (c) Triploblastic coelomate form. Mesodermally derived tissues completely surround the coelom. 26 Provide more Provide room for surface area for organ development diffusion of gases, nutrients, and gases Coelom: Advantages Provide an area for storage. Facilitate increased body size. Provide a vehicle for Often act as eliminating wastes hydrostatic and reproductive skeletons 27 12  9/12/24 Symmetry Asymmetry: The arrangement of body parts without central axis or point. Bilateral Symmetry: The arrangement of body parts such that a single plane passing between the upper and lower surfaces and through the longitudinal axis divides the animal into right and left mirror images. Radial Symmetry: The arrangement of body parts such that any plane passing through the oral-aboral axis divides the animal into mirror images. 28 Symmetry All invertebrates, except sponges, exhibit some type of body symmetry. 29 13  9/12/24 Cephalization Invertebrates with cephalization can respond to the environment in more sophisticated ways than can simpler invertebrates. 30 Early Development Invertebrates are either protostome or deuterostome Fate of the blastopore is important during early development. 31 14  9/12/24 EARLY DEVELOPMENT 32 Segmentation Annelids and Arthropods exhibit external segmentation The repetition of organs and tissues at intervals along the body of an animal, thus dividing the body into a linear series of similar parts or segments (metameres) 33 15  9/12/24 ANIMAL PHYLOGENY Echinoderm ata Chordata Arthropoda Annelida M ollusca Nem atoda Platyhelm ithes Cnidaria Porifera Copyright Pearson Prentice Hall 34 ANIMAL PHYLOGENY Copyright Pearson Prentice Hall 35 16  9/12/24 ANIMAL PHYLOGENY Copyright Pearson Prentice Hall 36 ANIMAL PHYLOGENY Copyright Pearson Prentice Hall 37 17  9/12/24 NEXT TOPIC: SURVEY OF THE ANIMAL KINGDOM 38 18