WFSC 302 1st EditionExam # 1 Study Guide Lectures: 1 - 6Lecture 1 (August 26)Taxonomy and Systematics Describe taxonomy. Compare extant to extinct. Who developed the binomial nomenclature system still used today? What’s Linnaean classification? Taxonomy:- Taxonomy is the science of biological nomenclature and classification.Extant vs. Extinct:- Extant: “living” vertebrates alive today. - Extinct: “having lived” vertebrates known only from the fossil record, no longer in existence.Carolus Linnaeus developed modern taxonomy and the binomial nomenclature system. Binomial is a two part name, Genus species. Linnaean classification is the method of using binomial nomenclature to designate species and categorize them into a hierarchy.KingdomPhylumClassOrderFamilyGenusSpeciesA good classification should be based on ancestor-dependent relationships among its own species, not on based on appearance (phenetic similarities)Describe Phylogenetic systematics. Who developed this method? What 3 groups compose a cladagram? How are phylogenies built?Phylogenetic systematics or cladistics is the method of arranging natural groups by determining the evolutionary relationships amongst species. Cladistics was developed by Willi Hennig. Thereare three groups recognized on a cladagram.1.Monophyletic groups- (clade) natural group that includes a most recent ancestor plus all of its descendants.2.Paraphyletic group- (grade) not a natural group, includes a most recent ancestor plus onlysome of its descendants.3.Polyphyletic group- an unnatural group; doesn’t include the most recent common ancestor of its members. Lecture 2 (August 28) What are the major groups of metazoan animals? What are the three subphyla of the Chordata? What are the embryological differences between craniates and other chordates?What is the significance of the Cambrian Period?Major groups of metazoan animals:1. Porifera: (sponges) No germ layers, no true tissues or organs, intracellular digestion.2. Eumetazoa: (all other animals) Germ layers present, true organs, tissues, mouth and digestive system.a. Radiate animals (Phyla Cnidaria & Ctenophora): radial symmetry, 2 germ layers.b. Bilateria : bilateral symmetry and 3 germ layersc.The three subphyla of Chordata are: Urochordata, Cephalochordata, and Craniata.The embryological differences that makes craniates different from other chordates: Craniates have homeobox genes, that regulate development, and a neural crest (a 4th germ layer).The Cambrian Period:- (Paleozoic Era) Known as the origin of Craniates.- The earliest non-tunicate “chordates” fossil record dated to this time.- Famous Cambrian deposits located at the Burgess Shale, Chengjiang, and Haikou.- Haikouella- famous fossil from the lower Cambrian. Possessed a neural cord , paired eyes, a relatively large three-chambered brain, an advanced circulatory system, and pharyngeal arch skeleton. Lecture 3 (September 2)What are the major groups of jawless fishes? Know that jawless craniates represent a paraphyletic group (“Agnatha”). Know the features when they first evolved and their significance to evolution of the vertebrates.-Myxiniformes (hagfishes)-Conodonts-Petromyzontiformes (lampreys)-“Ostracoderms”: also a paraphyletic group, some more closely related to gnathostomes (jawed vertebrates)-Exoskeleton: structure that surrounds the notochord and nerve cord. In early vertebrates arcualia surrounded the nerve cord.-Jaws: Hypothesis that they derived from gill arches. No fossil evidence for the transition from jawless to jaws. Thought to have been important for gill ventilation, and forceful ventilation, notpredation may have been the original role of the jaws.-Paired Fins: Jawless “ostracoderms” exhibited the first paired pectoral fins, which was the first occurrence of paired limbs among vertebrates. They enhanced mobility and pitch.Lecture 4 (September 4)Learn the major characteristics of the Gnathostomata. What are teeth? What are stem- and crown-groups? Know the major groups of cartilaginous fishes.Three major Gnathostomata characteristics:-Jaws: Placoderms were the first jawed vertebrates.-Three SSC’s: three semi-circular canals in the inner ear (anterior, posterior, and horizontal SSC’s) -Two pairs of paired appendages: allow more complex body movementsTeeth: the presence of is a synapomorphy of the Eugnathostomata. Teeth are hard mineralized structures of the dermis composed of a pulp of cavity surrounded by a layer of dentine, with an outer layer of enamel.Homodont & HeterodontTeeth of eugnathostomes, show a major advancement over the “teeth”Chondrichthyan dentition is known as polyphyodont, and their teeth are replaced throughout their lives.Stem-group: contain only fossil taxa that exhibit some but not all of the derived characters of the crown-group.Crown-group: Defined based on derived characteristics of extant taxa but may also contain fossils.Lecture 5 (September 9)What are the four synapomorpies of the Osteichthyes? What is the Devonian Period known for? Osteichthyes: Divided into two groups: Class Sarcopterygii (lobe-finned fishes) and Class Actinopterygii (ray-finned fishes). They are united based on four synapomorpies:1. Endochondral bone: bone that replaces cartilage developmentally.2. Gas-filled bladder: outgrowth of the anterior portion of the alimentary canal in Osteichthyes. It first served as a respiratory device for fishes. In Sarcopterygians it servesas a lung. In Actinopterygians it serves as a swimbladder.3. Fin rays: light weight dermal bones, lepidotrichia, that support the fins. In Sarcoptergians the rays of paired fins extend from a central shaft of bones in a feather-like manner. In Actinopterygians the rays of paired fins spread outward from bones at the base of the fins in a fan like manner.4. New jaw bones (maxilla and premaxilla): New dermal bones that were added to the jaw, the maxilla and premaxilla are part of the upper jaw, and allow a place for teeth to extend from.The Devonian Period: “age of the fishes”Many jawed and jawless fishes were found to be living at this time. During this period fossils of all the major lineages of fishes were found, including agnathans and gnathostomes. Several found in Devonian deposits didn’t make it past the Devonian.Lecture 6 (September 11)Describe the Sarcopterygii and Tetrapoda. Know of the two earliest stem group tetrapods.Sarcopterygii: -true enamel present, referred to as enamoloid. Sarcopterygii