PPT-Gnathostomes- "Jawed Fishes"

Appearance of Jaws Silurian 410430 million years ago before agnathan radiation value of jaws greater feeding opportunities new types of food mechanical digestion defense manipulate objects. 1. What is a fish?. Aquatic vertebrates that have paired fins, scales, and gills.. Of course there are exceptions . . There are approx. 24,000 living species. 2. Questions. What is the function of fins?. Notothenioid. Fishes. by: Priscilla Watson-Wynn. Antarctica. Fifth largest continent. The world’s most southern continent. Surrounded by Southern Ocean. 98% covered in ice sheet & 2% barren rock. The Fishes: Vertebrate Success in Water. Evolutionary Perspective. Phylogenetic Relationships. Subphylum Craniata. Skull surrounds brain, olfactory organs, eyes, and inner ear.. Infraphylum Hyperotreti. can be up to Leeches are used in plastic surgery to prevent bruising and in re- Cnidaria. Ctenophora. Rotifera. Nematoda. Nemertea. Mollusca. Annelida. Arthropoda. Bryozoa. Phoronida. Brachiopoda. Echinodermata. Chordata. No true tissues. radial symmetry. diploblastic. true tissues. - Reptiles and Mammals -. Amniote. Egg. Amnionic sac – protects embryo. Allantois – disposal sac for embryonic waste, works with chorion in gas exchange. Yolk sac – storage and transfer of nutrients to developing embryo. Fish- multiple fish that belong to the same species. Fishes- multiple fish that belong to different species. “Fish” versus “Fishes”. All . have…. At least one bone in their skeleton. Scales. Scientific Classification-. Class . Osteichthyes. Class . Osteichthyes. includes all bony fishes. . Like all fishes, . Osteichthyes. are cold-blooded vertebrates that breathe through gills and use fins for swimming.. Traditional organization of Vertebrate Taxonomy. AGNATHA -Jawless Fishes. CHONDRICHTHYES -Sharks, skates, rays and chimeras. OSTEICHTHYES -Bony Fishes. AMPHIBIA -Amphibians. REPTILIA -Reptiles. MAMMALIA -Mammals. Response of fishes to flow. Gido. and . Propst. 2010. Flow variation in the San Juan River. Flow variation in the San Juan River. 56 m. 3. /s ~2000 . cfs. 14 m. 3. /s . ~. 500 . cfs. Gido. and . Propst. Origin. Position. Anatomy. Ovaries. Testes. Testes in different groups. Structure of ovary. Structure of testes. Cyclic changes in gonads. Intermittent organs. Reproductive strategies. Acknowledgements . coloured. . . Colouration. is one of the most common phenomena found among the fishes.. The enormous range of . colours. and patterns that produced in fishes are generally related to their habits.. Page 39, . text. Precambrian. Phylogeny of the Fishes. The first vertebrates to appear in the fossil record occurred in the late Cambrian Period (. ~. 500 mya). These were jawless armored fishes known as . Prof. Dr. . Mohammad . Hamed. . Bahnasawy. .  . Prof. of fish . biology . Zoology Department. Faculty . of . Science. . Damietta . University. The negative aspects. 1- Poisonous and venomous fishes.