1. 10-1 CHAPTER 10 Taxonomy and Phylogeny of Animals Taxonomy and Phylogeny of Animals

2. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-2

3. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-3 Linnaeus and Taxonomy More than 1.5 million species of animals are named More than 1.5 million species of animals are named Estimated that these account for Estimated that these account for Less than 20% of all animals currently alive Less than 20% of all animals currently alive Less than 1% of extinct animals Less than 1% of extinct animals Taxonomy (aka - Systematics) Taxonomy (aka - Systematics) Formal system for naming and classifying species Formal system for naming and classifying species Science of classifying organisms based on similarity, biogeography, molecular components, development, etc. Science of classifying organisms based on similarity, biogeography, molecular components, development, etc.

4. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-4 Linnaeus and Taxonomy Greek philosopher Aristotle first classified organisms (350 BC) Greek philosopher Aristotle first classified organisms (350 BC) Carolus Linnaeus designed the current system of classification (1750) Carolus Linnaeus designed the current system of classification (1750) Swedish botanist with experience classifying flowers Swedish botanist with experience classifying flowers Used morphology (study of form and structure) to develop a classification system of animals and plants 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 Divided animal kingdom into species and gave each a distinctive name Grouped species into genera, genera into orders, and orders into classes 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 His classification scheme has been drastically altered, but the basic principle is still followed

5. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-5 Carolus Linnaeus

6. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-6 Hierarchy of taxonomic ranks now includes 7 major groups Hierarchy of taxonomic ranks now includes 7 major groups Kingdom, phylum, class, order, family, genus, and species Kingdom, phylum, class, order, family, genus, and species Now, the new level of Domain is also used. Now, the new level of Domain is also used. All animals are placed in Kingdom Animalia, or Domain Eukarya All animals are placed in Kingdom Animalia, or Domain Eukarya Taxa (Taxon) - Groups of animals that share a particular set of characteristics. Taxa (Taxon) - Groups of animals that share a particular set of characteristics. Example: True Flies “Diptera” - single pair of wings Example: True Flies “Diptera” - single pair of wings Each rank can be subdivided into additional levels of taxa Each rank can be subdivided into additional levels of taxa Superclass, suborder, etc. Superclass, suborder, etc. Linnaeus and Taxonomy

7. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-7

8. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Division of Life - Milestones

9. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 3 Domains - current proposal Based on ribosomal RNA sequences

10. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-10 Nomenclature: assignment of a distinctive name to each species Nomenclature: assignment of a distinctive name to each species A scientific name of an animal consists of two words (binomial nomenclature) A scientific name of an animal consists of two words (binomial nomenclature) First word is the genus and is capitalized First word is the genus and is capitalized Second is the species written in lower case Second is the species written in lower case Scientific name should be printed in italics or underlined if handwritten Scientific name should be printed in italics or underlined if handwritten Homo sapiens Homo sapiens Taxonomy

11. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-11 Some animals are subspecies, usually caused by Geographic locations. They are referred to as trinomials (3 names) Some animals are subspecies, usually caused by Geographic locations. They are referred to as trinomials (3 names) All three terms are in italics All three terms are in italics Subspecies is also in lower case Subspecies is also in lower case Taxonomy

12. 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 E.e. plantens, E.e. picta, E.e.croceater

13. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-13 Cladogram Cladogram Diagram illustrating hierarchy of clades (groups of animals with common ancestry) Diagram illustrating hierarchy of clades (groups of animals with common ancestry) Outgroups used Outgroups used Phylogenetic tree (compared to cladogram) Phylogenetic tree (compared to cladogram) Additional information concerning: Additional information concerning: ancestors, ancestors, duration of lineages, duration of lineages, amount of evolutionary change amount of evolutionary change (some mathematical calculation and numerical values usually invovled) Taxonomic Characters and Phylogenetic Reconstruction

14. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-14 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?

15. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-15 Sources of Phylogenetic Information Sources of Phylogenetic Information (What do we use to identify animals in a Phylogenetic Tree??) Comparative Morphology Comparative Morphology Examines shapes, sizes and development of organisms Examines shapes, sizes and development of organisms Skull bones, limb bones, scales, hair and feathers Skull bones, limb bones, scales, hair and feathers Living specimens and fossils are used Living specimens and fossils are used Taxonomic Characters and Phylogenetic Reconstruction

16. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-16 Comparative Biochemistry Comparative Biochemistry Analyzes sequences of amino acids in proteins and nucleotides sequences in nucleic acids Analyzes sequences of amino acids in proteins and nucleotides sequences in nucleic acids Comparative biochemistry can be applied to fossils Comparative biochemistry can be applied to fossils Comparative Cytology Comparative Cytology Examines variation in number, shape and size of chromosomes Examines variation in number, shape and size of chromosomes Used almost exclusively on living specimens Used almost exclusively on living specimens Taxonomic Characters and Phylogenetic Reconstruction

17. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-17 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.

18. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Animal Kingdom Patterns of Organization 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 Characteristics used to Classify:

19. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

20. 10-20 Major Subdivisions of the Animal Kingdom Traditional groupings based on embryological and anatomical characters Traditional groupings based on embryological and anatomical characters Branch (Parazoa): phylum Porifera, the sponges and phylum Placozoa Branch (Parazoa): phylum Porifera, the sponges and phylum Placozoa Branch (Eumetazoa): all other phyla Branch (Eumetazoa): all other phyla

21. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 10-21 Branch Eumetazoa Branch Eumetazoa Grade I (Radiata): phyla Cnidaria Grade I (Radiata): phyla Cnidaria Grade II (Bilateria): all other phyla Grade II (Bilateria): all other phyla Division A (Protostomia): Mouth is first opening Division A (Protostomia): Mouth is first opening Subdivision of Protostomes by coelom formation: Acoelomates: phyla Platyhelminthes, Acoelomates: phyla Platyhelminthes, Pseudocoelomates: phyla Nematoda, Pseudocoelomates: phyla Nematoda, Eucoelomates: phyla Mollusca, Annelida, Arthropoda Eucoelomates: phyla Mollusca, Annelida, Arthropoda Division B (Deuterostomia): Anus is first opening Division B (Deuterostomia): Anus is first opening phyla Echinodermata, Chordata phyla Echinodermata, Chordata Major Subdivisions of the Animal Kingdom