Chapter 4: Tetrapods

ornithischia

order of archosaurs; dinosaurs

ichthyostegalia

first tetrapods; evolved in water but could walk on land; were robust and had tail fins, large heads and large mouths

lepidosauria

infraclass of diapsids; order squamata contains all living lepidosaurs, 3000 species of lizards including snakes

archosauria

infraclass of diapsids; retains the two openings and also has openings in the bony palate; have marginal teeth; ancestors of birds

eutheria

infraclass of mammals; includes 17 surviving orders and 12 extinct orders; have placentas

paleognathae

infraclass of neornithes; includes ostriches, emus, cassowarys and large flightless relatives

neognathae

infraclass of neornithes; nearly all surviving birds

saurischia

order of archosauria; dinosaurs, some bipedal representatives

crocodilia

order of archosauria; only survivins archosaurs are crocodiles and relatives

thecodontia

order of archosaurs; widespread in triassic; may be ancestral to birds

cetacea

order of eutheria; among the most modified of mammals; include whales and dolphins

sirenia

order of eutheria; dugongs and manatees

edentata

order of eutheria; have simple or no teeth, includes anteaters, sloths and armadillos

hyracoidea

order of eutheria; hyraxes

lagomorpha

order of eutheria; include rabbits and pikas

primates

order of eutheria; includes lemurs, monkeys, apes, man

carnivora

order of eutheria; includes most flesh-eating mammals; includes bears, dogs, weasels, raccoons, civets, cats and hyenas

pinnipedia

order of eutheria; includes seals, sea lions, walruses

rodentia

order of eutheria; largest order; have gnawing incisors; include squirrels, beavers, rates, mice and porcupines

chiroptera

order of eutheria; only mammals capable of sustained flight; includes bats

insectivora

order of eutheria; small mammals with numerous sharp teeth; are the oldest and most primitive eutherians; include shrews, moles and hedgehogs

tubulidentata

order of eutheria; tubulidentata

proboscidea

order of eutheria; were once more prevalent in both number and in kinds; elephants

cynodontia

order of synapsids; ancestral to mammals; they chewed their food, had relatively long legs, had an upright stance and may have been warm blooded

anthracosaruia

subclass of amphibians; ancestors of reptiles; have teeth with infolded enamel (labyrinthodonts), deep skulls, and are large and stocky

allotheria

subclass of mammals; lived at the time of dinosaurs; not ancestral to other groups of mammals; were small herbivores or omnivores

prototheria

subclass of mammals; surviving members are in order monotremata and include the platypus and echidna; are oviparous

theria

subclass of mammals; viviparous; includes infraclasses metatheria (marsupials) and eutheria (placental mammals)

reptilia

class of vertebrates; evolved from anthracosaurian amphibians; most abundant vertebrates from the permian to the cretaceous eras; first class of tetrapods to have all structures necessary for fully terrestrial life: horny scales, claws, ribs that draw in air, and differentiated vertebral column that is firmly attached to the pelvic girdle

mammalia

class of vertebrates; have hair and mammary glands; 3000 genera known (2000 extinct)

aves

class of vertebrates; most homogenous and distinctive of all tetrapod classes; not very different from reptiles; likely evolved from reptile that was a slender, small carnivore/insectivore with long arms, legs, necks and tails; only vertebrates to be bipedal fliers (because of feathers)

archaeornithes

subclass of birds; includes archaeopteryx: the first known bird; had the capacity of flight but is unknown if it was an arboreal climber or a ground-living runner; fully feathered but had a lizard-like tail, separate clawed fingers and teeth in jaws

amphibia

(both kinds+life) class of vertebrates; evolved from lobe-finned ancestors; most abundant in carboniferous period; have large mouths, fleshy tongues, lungs, and eyelids and glands to moisten the eyes; some respiration occurs through the skin and the lining of the mouth and throat

artiodactyla

(even-toed) order of eutheria; includes pigs, camels, deer, antelopes and cattle

perissodactyla

(odd-toed) order of eutheria; includes horses, tapirs and rhinos

lissamphibia

(smooth) all surviving amphibians belong to this subclass; parts of skeleton are cartilaginous; includes orders anura (without+tail), urodela (having a tail), and apoda (legless)

pterosauria

(wing+lizard) flying reptiles

plesiosauria

aquatic; have broad bulky bodies, tapering tails, paddle-like limbs, blunt heads and sometimes long necks

enantiornithes

cretaceous birds; had fusions in hand skeleton, pygostyle, keeled breastbone, perching feet; were probably arboreal

ichthyosauria

dolphin-like body contours, fish-like tails, large eyes and large rostrum

testudinata

subclass of reptiles; includes turtles and tortoises; the shell, ribs, spine, toothless mouth and pectoral girdle are highly specialized; the skull, limbs and soft parts are primitive

anapsida

subclass of reptiles; no openings in bones of the temporal region; includes most primitive reptiles known

synapsida

subclass of reptiles; synapsid refers to skull having one opening bordered by postorbital and squamosal above; sometimes called mammal-like reptiles

diapsida

subclass of reptiles; two temporal openings in the skull; infraclass lepidosaura contains all surviving species of lizards

neornithes

subclass or birds; includes neognathae and paleognathae

tetrapod

vertebrate with four legs; typically terrestrial; has strong girdles, appendages and spines to resist gravity; lungs and pulmonary circulation replace gills; have overall modifications to function in air, i.e. eggs with shells and fetal membranes