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Vertebrate Natural History

Archosauria Archosauromorpha -BirdsAves Crocodylians (Crocodylia) Sauropsida Lepidosauromorpha Lizards and snakes (Squamata) Amniota Tuatara (Rhynchocephalia) Platypus and echidnas (Prototheria) Synapsida Tetrapoda (four feet) Thera Marsupial mammals (Metatheria Placental mammals (Eutheria Batrachia Lissamphibia Salamanders (Urodela) Rhipidistia -Frogs(Anura) Sarcopterygi Caccilians(Cymnophiona Osteichthyes (bony fishes) Gnathostomata (jawed mouths) Lungfishes Dipnoi Coelacanths Actinistia [Ray-finned fishes (Actinopterygi) Sharks, rays, and chimaeras (Chondrichthyes) Hagfishes and lampreys (Myxiniformes and Petromyzontiformes) Vertebrat Outgroups(tunicates end cephalochordates) /29:06 Fish Measurements FL SL fin base lengt Eyt dal length alfin base length Fish Measurements -Total length measured from the tip of the snout to the end of the tailfin. -General length is measured from the tip of the snout to the beginning of the tailfin. -Fork length is measured from the tip of the mouth to near the edge of the end of the tailfin. Fish Body Types "Standard Type" -- Moderately laterally compressed or spindle shaped in lateral profile (ex: Bass). Fusiform -- streamlined shape (constant swimming at high speeds like tuna, mackerels, etc.) Sagittiform -- slender with propulsive fins posteriorly located; ambush predators with high acceleration (ex: gars, pikes, barracudas). Anguilliform -- elongate and slender; efficient swimmers at low speeds/moving across a substrate (ex: eels). Compressiform -- laterally flattened and deep body with high maneuverability (ex: sunfishes). Globiform - short and robust bodies; substrate specialists capable of self-inflation (ex: puffers) Depressiform - flattened dorso-ventrally and wide-bodied; closely associated with substrate; often partially covered with bottom material and generally ambush predators (ex: stingrays and skates). Caudal Fin Types Heterocercal - upper lobe is supported by posterior section of the vertebral column; upper lobe > lower lobe (ex: sharks). Abbreviated heterocercal - upper lobe is slightly longer than the lower lobe (ex: bowfins). Not very common. Homocercal -- Vertebral column does not extend into the fin (most fishes = most common). Homocercal Fin Types 1. Lunate tail -- very fast fish, able to maintain high speeds for long periods of time, but a lack of surface area means that they can't stop or turn easily or swim backwards. 2. Forked tail -- cruising fish that swim continuously at a very fast rate (ex: tailor and Australian herring). Extra fin surface provides more maneuverability than fish with a lunate tail. Homocercal Fin Types Lunate tall:Very fast fish,able to maintain high speeds for long periods of time,but a lack of surface area means they can't stop or turn easily or swim backwards (e.g.tuna). Truncate tall Cruises at intermediate speeds,with increased manoeuvrability due to alarger surface area e.g. mangrove jack.Also able to accelerate quickly when needed Forked tail:Cruising fish that ryfast.rate /29:06 lity than fish with a ind able to accelerate quicklyforshort periods Mouth Shapes Terminal -- when upper and lower jaws meet at anterior extreme of the fish; usually active predators that run down prey. Mouth Shapes Subterminal/Inferior -- when upper jaw extends beyond lower jaw. Usually, benthic feeders that pick prey on or out of substrate (e.g., deep-sea spiny eels).