33.1    The Natural History of Reptiles

	Age of Amphibians was during the Carboniferous period.
	During this period, the first fossil record appeared
	Climate changes caused amphibians and stem reptiles to become extinct.
	Therapsids run faster than most reptiles.
	Therapsids were ancestors of mammals based on fossil evidence.
	Thecodonts were reptiles that stood up on two long, powerful hind legs.
	Dinosaurs' large body was an adaptation for maintaining a constant body temperature.
	Number of tuataras have declined because of the introduction of Polynesian rats.
	Scientists infer that snakes evolved from burrowing lizards.
	Burrowing lizards have long tube-shaped bodies without legs.
	Skinks and geckos can cast off their tails when grabbed by predators.
	Modern turtles and tortoises are direct descendents of stem reptiles.
	Sea turtles live in oceans.

33.2    Structure and Functions in Reptiles

	Keratin is insoluble in water.
	It acts as a barrier that prevents water from escaping the skin cells.
	Many reptiles shed their skin because the scales don't enlarge as the animal grows.
	Reptiles are carnivorous animals.
	Reptiles don't chew food.
	Food is digested by enzymes in stomach making it a long, slow process.
	Ectotherm - animal whose body temperature is determined by the environment.
	Spiny lizards maintain 34c body temperature by day simply by moving their body in relation to the sun.
	The partition between ventricles forms a four-chambered heart in crocodiles.
	Birds and mammals also have four-chambered hearts.
	Pit vipers have a special adaptation to help them find prey in the dark.
	A pit can detect a temperature change.

33.3    Reproduction and Development

	Generally, reptiles live in colder regions.
	They give birth to live young, although some species in warmer climates lay eggs.
	Depending on the species, some lay eggs in sand, soil or rotting logs.
	Eggs are laid where they can stay warm to ensure proper development.
	Reptilian young hatch looking like miniature adults.
	Although at risk from predators, the young are better equipped than fish or amphibian larvae for survival in its first months.

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