I. General Characteristics
Scales, dry skin, some w/ bony dermal plates
No larval stage, hard (leathery) shelled egg
Breathe through lungs
Legs with 5 toes, claws
Ectothermic (cold-blooded)
II. TuataraDistinctly different order (Rhynchocephalia)Nictitating membrane (3rd eyelid)Primitive skull structureLizard-like appearance, anatomically very different (very slow reproductive cycle)A true "living fossil"Found only on a few coastal New Zealand Islands
III. Turtles
Order Testudines225 species hard shell of overgrown ribsLack teeth - beakTerrestrial, (tortoise or box turtle)Semi-aquatic (terrapin)Marine (sea)
Turtles
Shell is really a bone, skin, and scale sandwich
Upper shell - Carapace
Lower shell - Plastron
Well developed senses
Most are herbivores or omnivores
Marine Turtles
All 7 species are endangered
Nest sites are being destroyed
Trapped and drowned in shrimp nets
Prized for food and shell
Turtles - Examples
See the lazerdisc
Classroom collection - Sulcata Tortoise
Painted Turtle
Red-eared Slider
Species AccountSpecies account of the _________________Vital Statistics ( scientific name, common name, taxonomy)Identification (shape, size, markings, general description)Habitat (biome and range)Behaviors (niche, feeding, when active, reproduction, etc.)Observations (details about our specimen)
IV. Crocodilians
Order Crocodilia, 3 families, 23 species
Crocodiles, alligators, caimans and gavials
laterally compressed tail, all semi-aquatic
4 chambered heart
scales reinforced with bony plates
teeth set in bony sockets
Crocodilians
Limited to tropics and sub-tropics
Female guards the nest
Both predator and scavenger, strongest stomach acid of any vertebrate
Am. Alligator saved by the Endangered Species Act
Adaptations – FROM THE VIDEO
V. Lizards
Order squamata, suborder sauria
3000 species
external ear opening, moveable eyelids
Tail in most readily detaches and regenerates
Lizards
Keen eyesight, most are insectivores
Males are territorial
Display with head bobs, pushup displays, etc.
Many are arboreal
VI. Behaviors - Thermoregulation
"cold-blooded" is more efficient
Reptiles warm up by behavior, basking
Pond turtles – out on logsSnapping turtle – at surfaceearless lizard - only head out of sandhorned lizard - changes colorSnakes on warm surfaces - roads
VII. SnakesOrder Squamata, suborder serpentes3000 speciesno external ears or eyelidsno legs, skutesspecially hinged jawForked tongue, Jacobsen's organMost are rodent eatersheat sensing pits and/or slit pupils in some
VIII. Snakes - Locomotion
Lateral UndulationMost common, most primitive, fish-like
Concertina Progressioncoiling and uncoiling like a slinky.
Rectilinear Locomotionusing just the skutes
Sidewindingadaptation to soft sand, desert.
IX. Snakes - Feeding"Bite and Swallow"
Most primitiveFound in garter snake and other aquatic and semi-aquatic snakes
ConstrictorsMost common
VenomousMost highly evolvedModified teeth, salivary glandsHemotoxins or neurotoxins