Biol276-Evo of Vert Life- Spring 2008-Fishes

Biol276-Evo of Vert Life- Spring 2008-Fishes - 2...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Diversity of Fishes outline I. Earth History from Origin of Multicellular through the “age of fishes” Age of Earth: 4.6 billion years Precambrian Era Paleozoic Era: Cambrian: Myllokunmingia and Haikouichthys Ordovician: Fossilized vertebrates are abundant Silurian: Diversification of fishes Devonian: "The Age of Fishes" Carboniferous: Rise of Tetrapods Permian: Diversification of modern fish (neopterygii) Mesozoic Era: "Age of Reptiles" Cenozoic Era: "Age of Mammals" MAJOR radiation of the Teleost fishes II. Paleozoic fish Craniata = Hagfish and Craniates Important note: Pharyngeal slits = gill slits, since the arches of tissue between slits contain gills. Vertebrata Important synapomorphies include: 2 pairs of vertical semicircular ducts Vertebrae Fossils occur in marine and freshwater deposits 1) Lampreys 2) Heterostracans 3) Osteostracans Gnathostomata Important synapomorphies include: Jaws gill slits (5-6) Paired Nostrils 3 rd pair of semicircular ducts First fossils are from freshwater deposits 1) Placoderms
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 2) Chondrichthyes 3) Acanthodii Osteichthyes – Well ossified internal skeletons, thin bony scales, paired lungs or swim bladder Actinopterygii – Ray finned fish, Single dorsal fin, Huge radiation in the Devonian and Silurian Chondrostei – sturgeons Neopterygii: 1) Bowfins and gars 2) Teleosts: most extant fish that aren’t sharks; make up half of all vertebrate species Sarcopterygii – muscular fins Monobasic fin - Contains stylopod: the humerus or femur 2 dorsal fins 1. Coelocanth 2. Lungfish 3. Tetrapods III. Summary of major clades: Synapomorphies Craniata – Chordates with braincase Vertebrata – Craniates with a backbone. Gnathostomata – Vertebrates with jaws Chondrichthyes – Gnathostomes with loss of bone in skeleton Osteichthyes – Gnathostomes with bony internal and external skeletons Sarcopterygii – Osteichthyans with muscular lobe fins Actinopterygii – Osteichthyans with bony, rayed fins...
View Full Document

This note was uploaded on 09/08/2008 for the course BIOL 276 taught by Professor Johnson during the Spring '07 term at UNC.

Page1 / 2

Biol276-Evo of Vert Life- Spring 2008-Fishes - 2...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online