ZOOL 224 Final Terms

Lissamphibia

• Two types of sensory papilla in inner ear, two separate channels to transmit vibrations to inner ear, green rods in the eye, pedicellate teeth, two types of multicellular skin glands, levator bulbi muscle.

Gymnophiona 

• Cylindrical, segmented bodies, tail short or absent, most fossorial, others aquatic, limbless, lost pectoral and pelvic girdles, blunt head, underhung lower jaw, degenerate eyes.

Caudata or urodela 

• Low slung bodies, moderate limb length, long tails, broad heads with distinct neck, distinct eyes, about half terrestrial half aquatic, some (aquatic) with reduced limbs.

Anura

• Completely adapted for saltatory locomotion, short body, broad head, no neck, no tail, well developed limbs, few entirely aquatic.

Sauropsida

• Many bipedal, flow through respiration system in lungs, urinary system, secrete uric acid.

Synapsida

• Mostly quadrupedal, tidal flow in lungs, no muscular diaphragm to aid in ventilation, secrete urea.

Testudines

• Shells, no teeth, no temporal fenestrae, shoulder girdle inside rib cage, neck vertebrae modified for being inside shell, head withdrawal, single copulatory organ in males, all lay eggs on land.

Lepidosauria

• Typically quadrupedal, diapsid or modified diapsid skulls, tendency to shed, cloacal slit is transverse rather than longitudinal.

Sphenodontia

• Lizard-like but not a lizard, unmodified diapsid skull, about 60cm long, ribs with overlapping uncinate processes, gastralia, no male copulatory organ, retain parietal eye covered by scales.

Squamata

• Lizards, snakes, and amphisbaneans, streptostyle - kinetic movements in the skull permitted by rotation of the quadrate bone, paired male copulatory organs, no gastralia, modified diapsid skull, bar of bone below the lower temporal fenetra is lost.

Mammalia

• Larger brain, higher metabolic rate, first very small.

• Cranial and postcranial skeleton, parasagittal stance/gait, greater flexion of the vertebral column, steeply angled zygapophyses prevent lateral flexion, hind limbs become more vertical, ilium extends anteriorly and posteriorly, reduced tail, astragulus becomes integrated with the tibia-fibula and calcaneum with the foot, evolution of diphyodonty, dentition with incisors, canines, and molars.

Monotremata

• Sprawling posture, endothermic but body temperature is less stable than most therian mammals, very specialized despite primitive mode of reproduction, lay eggs, walk with limbs in a semi-erect posture

Marsupalia

• Maternal abdominal pouch, foetal yolk sac with the chorion serves as placenta, give birth to underdeveloped young, incubated and nursed after birth in mothers pouch.

Placentalia

• Majority of mammals, birth of live young at a more advanced developmental stage, complex connection between mother and feotus

Theria 

• Viviparity, mothers immune system changes to prevent rejection of embryo, amniotic egg.

Morganucodon

• Basal mammal, chipmunk sized, large head, turbinals in nasal capsule, secondary palate, skull reflects enlarged area of brain, large cochlea, stapes articulates with quadrate, post-dentary bones still present.

Indohynus : 

• Eocene, SE Asia, missing link to whales, bones indicate habitually aquatic but also rarely fed in water.

Pakicetus : 

• 48 mya, wolf sized, unmodified pectoral and pelvic girdles, long slender limbs.

Ambulocetus : 

• Middle eocene, 47.8-40.3 mya, reduced limbs, large feet, normal tail, extensive dorso-ventral flexion and extension.

Remingtonocetus : 

• Hind limbs probably not weight bearing, fused sacrum, limited tail-powered locomotion, powerful hip extensors and femoral adductors.

Protocetidae : 

• Limbs comparable to ambulocetus, larger feet, probably webbed, terrestrial locomotion seal like, first stage of posterior shift of nostrils.

Georgiacetus : 

• 40 mya, southern USA, pelvis present but detached from vertebral column.

Basilasaurus and durodon : 

• 41.3-48 mya, tailfins likely present, hindlimbs reduced, elbow joints lockable.

Amphibia : 

• Amphi means two, bios means life.

Paedomorphosis : 

• Adults retain larval characteristics, neotyny means delayed somatic development compared to reproductive organs, progenesis means accelerated development of reproductive organs compared to body.

Sirendae : 

• Four american species, elongate, aquatic, retain gills as adults, lack hindlimbs, presence of lateral line system.

Cryptobranchidae : 

• Aquatic throughout life, small eyes, thin skin folds.

Ambystomatidae : 

• Mole salamanders, heavy bodied, heavy tails, courtship in water, paedomorphic axolotl.

Proteidae : 

• Southeast europe and North America, prominent external gills but also small lung.

Amphiumidae : 

• One genus, three species, eel like with weakly developed limbs, paedomorphic traits in adults, lungs present, costal grooves present, internal fertilization.

Plethodontidae : 

• Mostly North and South America, generalized body form as typical salamander, some have small limbs and elongate body, absence of larval stage, nasolabial grooves for chemosensory, connected to the vomeronasel organ, ground tapping behaviour, no lungs or gills, relies on subcutaneous respiration, tongue highly modified in some.

Pipidae : 

• Highly aquatic, dorsoventrally flattened, retain lateral line system, strongly webbed feet, digits of forefeet elongate, tactile sensory tips.

Scaphiopodidae : 

• Small limbs, vertical pupils, tough keratinous spades on their feet for digging.

Hylidae : 

• Tree frogs, geographically widespread, small body size, reduced or no webbing between digits, eyes face more forward, round bulbous pads at ends of digits to improve grip, adopt wide stance.

Dendrobatidae : 

• Poison dart frogs, south and central america, generally small body size, aposematic colours with high level of toxin.

Bufonidae : 

• True toads, Asia, Africa, North and South America, typically short legs, no theeth, large parotid gland.

Ranidae : 

• True frogs, nearly world wide, pointed head, eyes face mostly forward, well developed hind limbs for jumping.

Amniotic egg : 

• Controlled exchanges with the environment, amnion is fluid filled sac around embryo, allantois is storage of waste, chorions is respiratory gas exchange, packaged in calcareous or leathery shell.

Cheloniidae : 

• Depressed fusiform carapace, compact streamlined forelimbs, head/necks largely non retractable, worldwide subtropical to tropical with seasonal migrations to temperate zones.

Chelydridae : 

• 3 genera, aquatic carnivores, large heads, large bodies, stout limbs, flattened rigid carapace, reduced plastron, tail exceptionally long.

Emydidae : 

• Terrestrial through semi-aquatic, fresh water and estuarine, small to moderate size, omnivorous but prefer meat, 

Testudinidae : 

• Most diverse, widespread, arid terrestrial to totally aquatic, columnar hind limbs, high carapaces, full retraction of limbs, head and tail, forelimbs large and heavily scaled.

Sphenodontidae : 

• Ribs with overlapping uncinate processes, gastralia, no tympanum, no male copulatory organ, retain parietal eye.

Tuatara : 

• Special arrangement of teeth (propalineal), eat mainly invertebrates and some small vertebrates, active at night with body temperatures of 6 to 16 degrees celsius, only in new zealand, live in burrows in coastal forest or scrub, most active in warm wet weather.

Helodermatidae : 

• One genus, two species, large, heavy bodied, carnivorous, osteoderms of rounded scales, no tail autonomy, only lizard with venom glands in lower jaws, several ducts open between teeth and lips, teeth grooved not hollow.

Varanidae : 

• Monitors, goannas, earless monitors, africa, asia, australia, no caudal anatomy, no limb loss, carnivores with seasonal fruit, detect airborne volatile oils from decomposing carcasses.

Chameleonidae : 

• Africa, middle east, madagascar, souther spain, sri lanka, india, projectile tounges, independant eye movements, mostly arboreal and highly adapted for it, zygodactylous feet, skin of small juxtaposed scales, ability to change colours.

Iguanidae : 

• Americas, madagascar, west central pacific islands, small to large, variety of scales, terrestrial, arboreal, rock dwelling.

Gekkonidae : 

• Over 1000 species, pan-tropic on all land masses, loose fitting velvety skin with small juxtaposed scales, caudal anatomy common, small to large body size, large eyes with transparent spectacle, round pupils (diurnal) or vertical (nocturnal), tails vary greatly.

Scincidae : 

• 1200 species, very diverse, small to large, world wide, range from strong limbs to no external limbs, caudal anatomy common, head usually with large plates.

Opisthoglyphous : 

• Rear fanged.

Proteroglyphous : 

• Front fanged.

Solenoglyphous : 

• Channel/tube fanged.

Undulatory : 

• Use ventral scutes to grip ground to move forwards while lifting body off ground to reduce friction.

Sidewinding : 

• Limits contact with ground, best for hot surfaces.

Concertina : 

• Anchors some portions of body then pulls or pushes with other portions in direction of travel.

Rectinilear : 

• Rib (scale) walking.

Alligatoridae : 

• Tropical, American, freshwater, mandibular teeth fit inside upper jaw.

Crocodylidae : 

• World wide, tropical fresh and nearshore marine, variable snout shape, lingual salt glands, 4th mandibular tooth on each side exposed externally when mouth closed.

Gavialidae : 

• Gharial and false gharial.

Paleognathae : 

• Keeled sternum, can fly weakly, reduced wings.

Neognathae : 

• Galliformes, anseriformes, neoaves.

Hunting owls : 

• Mainly nocturnal, excellent vision, ears lack obvious external structure, filamentous feathers of facial disc, left and right ears are asymmetrical in position, skull in some species are also asymmetrical, comb like serrations on leading edge of wing feathers, can rotate head 270 degrees, single occipital condoyle, can’t smell, can’t rotate eyes.

Consequences of endothermy : 

• Need improved respiratory and circulatory systems, requires large food supply, more rapid and efficient digestion.

Procynosuchus : 

• Primitive cynodont, upper permian, multicuspid cheek teeth, temporal openings huge, lower temporal bar lateral to tooth rows, masseteric fossa on lateral surface of dentary.

Thrinaxodon : 

• Acetabulum opens more anteriorly and ventrally, proximal femoral head angled to shaft, allows femur to be directed more vertically and to swing in a wider arc, dentition with incisors, canines, and molars, molars are replaced regularly and no specific pattern of occlusion, dentary largest lower jaw bone, big coronoid process, postdentary bones small, not sutured to dentary, quadrate small, loosely attached to squamosal

Paradox of probainognathus : 

• Increased power of jaws, decreased strength of postdentary bones and quadrate, origin of mammalian middle ear.

Didelphimorphia : 

• Opossums, south and central america to mexico, most primitive, generalized.

Paucituberculata : 

• Caenolestidae, shrew opossums, south america, thick fur, small eyes, females lack pouch, tails long, not prehensile.

Microbiotheria : 

• Monito del monte, chile and argentina, well developed pouch in females, opposable pollex and hallux.

Dasyuromorphia : 

• Australia, new guinea, numbats, tasmanian wolf, dasyurids, many lack a full pouch.

Notoryctemorphia : 

• Marsupail moles, australia, new guinea, vesitigial eyes, no external ears, short stout tails, foreclaws modified for digging.

Peramelemorphia : 

• Australia, new guinea, bandicoots, bilbies, 100g, to 5kg.

Diprotodontia : 

• Australia, new guinea, wallabies, kangaroos, possums, koalas, wombats, gliders, potoroos, rat kangaroos.