Tedra McNairApril 22, 2009

Period, 2

Chapter 31 Reptiles and Birds

Evolution of Reptiles

• Reptiles evolved from amphibian-like ancestors. Reptiles have evolved into unique forms such as:

Turtles, snakes, and dinosaurs, but they also have taken on the appearance and habits of other vertebrate groups, such as sharks and dolphins.

Form and Function in Reptiles

-Reptiles eat a wide

variety of foods.

-Reptiles have two spongy

lungs that provide more

gas-exchange area than

those of amphibians.

However snakes only have

one.

Respiration

Feeding

What Is A Reptile?What Is A Reptile? A A reptile reptile is a vertebrate that has dry, scaly skin, is a vertebrate that has dry, scaly skin,

lungs, and terrestrial eggs with several lungs, and terrestrial eggs with several membranes.membranes.

Form and Function in Form and Function in ReptilesReptiles

ReproductionReproduction

Reptiles reproduce byReptiles reproduce by

internal fertilization. This is internal fertilization. This is

where the male depositswhere the male deposits

sperm inside of female.sperm inside of female.A reptilian egg is created to A reptilian egg is created to

protect the embryo from protect the embryo from

drying out. This egg is drying out. This egg is

called an amniotic (am-nee-called an amniotic (am-nee-

AHT-IK) egg.AHT-IK) egg.

The Last SurvivorsThe Last Survivors

• The four surviving groups of reptiles are lizards and snakes, crocodilians, turtles and tortoises, and the tuatara (too-uh-TAH-ruh)

What Is a Bird?• Birds are reptile-like

animals that maintain a constant internal body temperature. They include the following:

• An outer covering of feathers

• Two legs that are covered in scales and are used for walking and perching.

• Front limbs modified into wings.

Form, Function, and FlightBody Temperature Control

Unlike reptiles, birds can

generate their own body heat.

Animals that generate their

own body heat are called

endotherms.

Feeding

Any body heat that a bird loses

must be regained by eating

food. The more food a bird

eats, the more heat energy its

metabolism can generate.