Section

4 Reptiles

ObjectivesAfter completing the lesson, students will be able toB.3.4.1 Identify adaptations that allow reptiles to live on land.B.3.4.2 Contrast the characteristics of each of the three main groups of reptiles.B.3.4.3 Describe one adaptation that helped dinosaurs survive before they went extinct.

Target Reading SkillIdentifying Main Ideas Explain that identifying main ideas and details helps students sort the facts from the information into groups. Each group can have a main topic, subtopics, and details.

AnswersPossible answers:Main idea—Reptiles are adapted to conserve water.Details—Reptiles have a thick, scaly skin that prevents water loss; reptile eggs have a shell and membranes that keep them from drying out; reptile’s kidneys concentrate wastes before excreting them so that little water is lost.

Teaching Resources

• Transparency B30

Preteach

Build Background KnowledgeConsidering Snake CharacteristicsAsk: What are some characteristics of snakes? (Students may say no legs, poisonous, or fangs) List students’ answers on the board. After students have become familiar with the information in the section, revisit this list. Help students to decide which of the characteristics are facts, which are true of some snakes, and which are myths.

L2

Skills Focus Inferring

Materials sock with ribbed cuff, grapefruit, strong rubber band

Time 10 minutes

Tips Students can compare estimated diameters of the unstretched sock and the grapefruit. During Step 2, use a rubber band that is too small to fit around the

L1 grapefruit. Reinforce the lesson by showing students a picture of a snake skull, pointing out the lack of large regions of solid bone.

Think It Over Students should infer that the spreading jawbones of the snake allow it to eat larger prey than would be possible with firmly joined jawbones.

4 Reptiles

How Do Snakes Feed?1. To model how a snake feeds, stretch

a sock cuff over a grapefruit “prey” by first pulling on one side and then on the other. Work the grapefruit down into the “stomach.” A snake’s jawbones can spread apart like the sock cuff.

2. Remove the grapefruit and put a rubber band around the sock about 8 centimeters below the opening. The rubber band represents the firmly joined jawbones of a lizard. Now try to repeat Step 1.

Think It OverInferring What is the advantage of having jawbones like a snake’s?

Reading PreviewKey Concepts• What are some adaptations that

allow reptiles to live on land?

• What are the characteristics of each of the three main groups of reptiles?

• What adaptation helped dinosaurs survive before they became extinct?

Key Terms• reptile• kidney• urine• amniotic egg

Target Reading SkillIdentifying Main Ideas As you read the information under the heading titled Adaptations for Life on Land, write the main idea in a graphic organizer like the one below. Then write three supporting details that give examples of the main idea.

The king cobra of Southeast Asia is the world’s longest venom-ous snake. It can grow to more than 4 meters long. When itencounters a predator, a king cobra flattens its neck and rearsup. Its ropelike body sways back and forth, and its tongue flicksin and out.

A king cobra’s fearsome behavior in response to a predatorcontrasts with the gentle way it treats its eggs. King cobras areone of the few snakes that build nests. The female builds a nestof grass and leaves on the forest floor. She laysher eggs inside the nest and guards themuntil they hatch.

King cobra �

Detail Detail Detail

Main Idea

Reptiles are adapted to conservewater.

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Instruct

Adaptations for Life on Land

Teach Key ConceptsInvestigating Reptilian AdaptationsFocus Tell students that land animals are adapted to environmental conditions that differ from those of aquatic animals.

Teach Call on student volunteers to discuss how reptilian adaptations differ from those of amphibians. Ask: How do the two groups differ in egg laying? (Reptiles lay eggs on land that are protected from drying out; amphibians lay eggs in water.) How and why are their skins different? (Amphibian skins are moist, because amphibians obtain oxygen through the skin; reptilian skins are dry and scaly—they breathe solely with lungs—and able to prevent water loss.)

Apply Ask: Do sea turtles have amphibian or reptilian adaptations? (Reptilian: sea turtles breathe with lungs and lay eggs out of water.) learning modality: verbal

Teaching Resources

• Transparency B31

Independent PracticeTeaching Resources

• Guided Reading and Study Worksheet: Reptiles

Apply Why might wet skin not be practical for a snake? (Snakes do not live in water, so having to keep the skin moist would be difficult.) learning modality: logical/mathematical

For: More on reptilesVisit: PHSchool.comWeb Code: ced-2034

Students can review reptiles in an online interactivity.

L2

L2

PHSchool.com

Adaptations for Life on LandLike other reptiles, king cobras lay their eggs on land ratherthan in water. A reptile is an ectothermic vertebrate that haslungs and scaly skin. In addition to snakes such as the kingcobra, lizards, turtles, and alligators are also reptiles. Unlikeamphibians, reptiles can spend their entire lives on dry land.

The ancestors of modern reptiles were the first vertebratesadapted to life completely out of water. Reptiles get their oxy-gen from air and breathe entirely with lungs. Reptiles that livein water, such as sea turtles, evolved from reptiles that lived onland. So, even though they live in water, they still breathe withlungs and come ashore to lay eggs.

You can think of a land animal as a pocket of water heldwithin a bag of skin. To thrive on land, an animal must haveadaptations that keep the water within the “bag” from evapo-rating in the dry air. The skin, kidneys, and eggs of reptilesare adapted to conserve water.

Skin and Kidneys Unlike amphibians, which have thin,moist skin, reptiles have dry, tough skins covered with scales.This scaly skin protects reptiles and helps keep water in theirbodies. Another adaptation that helps keep water inside a rep-tile’s body is its kidneys, which are organs that filter wastesfrom the blood. The wastes are then excreted in a watery fluidcalled urine. The kidneys of reptiles concentrate the urine sothat the reptiles lose very little water.

What are two functions of a reptile’s skin?

PHSchool.com

For: More on reptilesVisit: PHSchool.comWeb Code: ced-2034

FIGURE 18A Desert Tortoise The tough, scaly skin of this desert tortoise helps it survive in a dry environment.

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Making Inferences About Eggshells

Materials small, cut pieces of a sponge; plastic bag; water

Time 10 minutes over two class periods

Focus Challenge students to make inferences about how eggshells and membranes prevent fluid loss.

Teach Have students work in small groups; provide each group with two pieces of sponge and one resealable plastic bag that will model an egg’s shell and membranes. Have students wet both sponge pieces thoroughly. Then put one piece in the plastic bag. They should place the other piece of sponge on top of the sealed bag and leave it overnight. The next day, ask students to describe the condition of their sponges. (The sponge outside the bag is much drier and more rigid.)

Apply Lead students to infer that the condition of the sponges left outside the bag is similar to what would happen to a developing embryo if the egg did not have a shell and membranes that retain moisture. learning modality: visual

Student Edition on Audio CD

Address Misconceptions

Investigating Snake SkinFocus Snake skins are dry, not slimy.

Teach Some students may think snake skins are slimy. A snake’s skin is actually quite dry, especially compared to that of a fish or amphibian. Under supervision, you may allow students to touch the scales of a molted snake skin. They should wash their hands afterward.

L1

Monitor Progress L2

Skills Check Using Figure 19, point out the membranes of a tortoise egg and call on students to tell the function of each.

AnswersFigure 19 Shell, membrane surrounding embryo

The scaly skin protects the reptile and prevents water loss.

The shell protects the embryo and haspores that oxygenand carbon dioxidecan pass through.

Fluid within this membranecushions the embryo and keeps it moist.

Oxygen and carbon dioxide move acrossthis membrane.

The embryo‘s wastescollect inside thismembrane.

This membrane holds the yolk, which is the embryo‘s energy supply.

Embryo

An Egg With a Shell Reptiles have internal fertilizationand lay their eggs on land. While still inside a female’s body,fertilized eggs are covered with membranes and a leatheryshell. Unlike an amphibian’s egg, a reptile’s egg has a shell andmembranes that protect the developing embryo and help keepit from drying out. An egg with a shell and internal membranesthat keep the embryo moist is called an amniotic egg. Pores inthe shell let oxygen gas in and carbon dioxide gas out.

Look at Figure 19 to see the membranes of a reptile’s egg.One membrane holds a liquid that surrounds the embryo. Theliquid protects the embryo and keeps it moist. A second mem-brane holds the yolk, or food for the embryo. A third mem-brane holds the embryo’s wastes. Oxygen and carbon dioxideare exchanged across the fourth membrane.

FIGURE 19

The Amniotic EggThe membranes and shell of an amniotic egg protect the developing embryo. Relating Cause and Effect Which parts of an amniotic egg help keep the embryo from drying out?

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Lizards and Snakes

Teach Key ConceptsCharacteristics of Lizards and SnakesFocus Direct students to Figure 20.

Teach Ask: What are the chameleon’s adaptations that make it a successful predator? (Sticky tongue that moves rapidly, claws that allow movement up trees, tail that grips, eyes that swivel, skin that changes color to match background) How is the chameleon’s skin like that of all reptiles? Why is it like this? (Dry and scaly, to prevent water loss) Name two ways lizards differ from snakes. (Lizards have four legs, moveable eyelids, and two lungs; snakes have no legs or eyelids and only one lung.)

Apply Ask: What is the term for animals with a diet similar to most reptiles? (Carnivores) Besides assisting in obtaining food, what other benefit does the ability to blend into its surroundings offer a chameleon? (Makes it easier for chameleons to hide from their own predators) learning modality: visual

Address Misconceptions

Investigating Venomous SnakesFocus Tell students that venomous snakes are not necessarily aggressive.

Teach Students may mistakenly believe that venomous snakes are vicious and aggressive. Point out that although people rightly fear being bitten by venomous snakes, the most venomous snakes are not aggressive toward humans. Normally, they will bite a person only when cornered or startled. Snake venom is primarily an adaptation for capturing prey, not for defense.

Apply Ask: If you do not know whether a snake you see is venomous, what should you do when you come upon it? (Possible answer: Move away in a nonthreatening manner.) learning modality: verbal

L2

L1

Moveable EyelidsA chameleon has moveable eyelids that close, keeping its eyes moist. Its two eyes can move in different directions at the same time, helping the chameleon find food and protect itself.

SkinThe chameleon’s skin is covered with overlapping scales. A chameleon can camouflage itself by changing its skin color.

TongueA chameleon can shoot out its tongue to capture prey.

ClawsSharp claws help chameleons climb trees and grip branches.

Long TailA chameleon coils its tail tightly around branches, giving it extra grip.

Leg A chameleon uses its legs to move.

Lizards and SnakesMost reptiles alive today are either lizards or snakes. These twogroups of reptiles share some important characteristics. Bothlizards and snakes are reptiles that have skin covered withoverlapping scales. As they grow, they shed their skin andscales, replacing the worn ones with new ones. Most lizardsand snakes live in warm areas.

Lizards differ from snakes in an obvious way. Lizards havefour legs, usually with claws on the toes, and snakes have no legs.In addition, lizards have long tails, external ears, movable eyelids,and two lungs. In contrast, snakes have streamlined bodies,no external ears, and no eyelids, and most have onlyone lung. You can see the characteristics ofa lizard in Figure 20.

FIGURE 20

Characteristics of a LizardThis lizard, a Jackson’s chameleon, has many adaptations that help it survive in its environment.

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Differentiated Instruction

Gaining a Closer Perspective on Snakes

Materials

live snake(s), skilled handler(s)

Time

40 minutes

Focus

Arrange a presentation in which students can “meet a snake,” either by taking students to a zoo, or by inviting a guest presenter to your class.

Teach

Have students write a checklist of key features to observe. If possible, arrange for students to observe the movement of snakes across a variety of surfaces. Refer to Enrich:

Reptiles

in Teaching Resources for information on various types of snake movement. Ask students to describe the kinds of movement they observe. Some students may be fearful of snakes; allow fearful students to observe from a distance. Make sure the snakes are from nonvenomous and nonaggressive species. Garter and grass snakes are common and can be easily and safely handled.

Apply

Ask:

Besides its movement, what snake or reptilian characteristics do you observe in the snake?

(No legs, no eyelids, scaly skin.)

learning modality: visual

L1

Gifted and Talented

Describing Reptiles

Challenge students to create a crossword puzzle with answers gained from the figures and text covered under the Lizards and Snakes heading.

(Example: A chameleon catches prey on the _ _ _ _ _ _ tip of its tongue [sticky].)

learning modality: logical/mathematical

L3

Less Proficient Readers

Identifying Reptile Facts

Pair up students needing help reading the section on reptiles with the Gifted and Talented students completing the crossword exercise. Have each of the less proficient readers review the text and figure descriptions to locate answers to their partners’ crossword puzzle.

learning modality: visual

L1

Monitor Progress L2

Writing

Ask students to write a paragraph that describes how snakes move.Students can save their paragraphs in their portfolios.

Answers

Figure 21

Lizards—four legs, some are herbivores, all have two lungs and movable eyelids; Snakes—no legs, all are carnivores, most have only one lung, no eyelids.

They walk and run usingtheir legs.

Obtaining Food A few lizards are herbivores that eatleaves. Most lizards, however, are carnivores that cap-ture their prey by jumping at it. While some large liz-ards will eat frogs and birds, most smaller lizards areadapted to hunt insects. For example, chameleons havesticky tongues adapted for snaring insects.

All snakes are carnivores. Most snakes feed on smallanimals, such as mice, but some eat large prey. If youdid the Discover Activity, you learned that a snake’s jaw-bones can spread wide apart. In addition, the bones of asnake’s skull can move to let the snake swallow an ani-mal larger in diameter than itself. Snakes capture theirprey in different ways. For example, some snakes havelong, curved front teeth for hooking slippery prey.Other snakes, such as rattlesnakes and copperheads,have venom glands attached to hollow teeth calledfangs. When these snakes bite their prey, venom flowsdown through the fangs and enters the prey.

Movement While lizards walk and run using theirlegs, snakes cannot move in this way. If you’ve ever seena snake slither across the ground, you know that when itmoves, its long, thin body bends into curves. Snakesmove by contracting, or shortening, bands of musclesthat are connected to their ribs and their backbones.Alternate contractions of muscles on the right and leftsides produce a slithering side-to-side motion. Insteadof slithering, sidewinder snakes, like the one shown inFigure 22, lift up their bodies as they move.

How do lizards move?

FIGURE 22A Sidewinder Snake This sidewinder snake lifts loops of its body off the desert sand as it moves along. Only a small part of its body touches the sand at one time.

FIGURE 21An Egg-Eating Snake The jawbones of this snake’s skull have moved to let the snake swallow an egg. Making Generalizations How are snakes different from lizards?

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Alligators and Crocodiles

Teach Key ConceptsInvestigating Large Reptilian PredatorsFocus Tell students that alligators and crocodiles are known for their size, predator skills, and care of their young.

Teach Pace off 5 meters in your classroom to demonstrate to students the size of the largest alligators and crocodiles. Ask: What traits make these animals successful predators? (Hunting at night when they are concealed, strong tail for rapid swimming, muscular jaws, many sharp teeth)

Apply Ask: Can you think of other vertebrate predators that share some of the alligator’s and crocodile’s traits? (Sharks are strong, fast, and large, have pointed teeth, and eat large prey; frogs and lizards sneak up on prey.) learning modality: verbal

Turtles

Teach Key ConceptsExploring Adaptations of TurtlesFocus Remind students that a turtle is a reptile.

Teach Ask: Where do turtles live? (On land [tortoises] and in salt and fresh water) Do sea turtles have gills? (No, all turtles breathe with lungs.) What is a turtle shell made from? (The ribs and backbone) Without teeth, how do turtles feed? (Their sharp beaks tear food.)

Apply Ask: Do you think land turtles move quickly? (No) Then how do they escape predators? (By drawing into their protective shells) learning modality: verbal

L2

L2

ReptilesShow the Video Field Trip to help students understand reptile adaptations. Discussion question: Describe two adaptations that allow crocodiles to remain underwater for long periods of time. (Their heart rates slow down; some of the valves that control blood flow close. This diverts blood away from the lungs, where it isn’t needed and sends it to the brain and other organs where the blood is essential.)

Alligators and CrocodilesIf you walk along a lake in Florida, you just might see an alliga-tor swimming silently in the water. Most of its body liesbeneath the surface, but you can see its large, bulging eyesabove the surface. Alligators, crocodiles, and their relatives arethe largest living reptiles. Both alligators and crocodiles arelarge, carnivorous reptiles that care for their young. So, howdo you tell an alligator from a crocodile? Alligators have broad,rounded snouts, with only a few teeth visible when theirmouths are shut. In contrast, crocodiles have pointed snouts,with most of their teeth visible when their mouths are shut.

Obtaining Food Alligators and crocodiles are carnivoresthat often hunt at night. They have several adaptations for cap-turing prey. They use their strong, muscular tails to swim rap-idly. Their jaws are equipped with many large, sharp, andpointed teeth. Their jaw muscles are extremely strong whenbiting down. Although alligators will eat dogs, raccoons, anddeer, they usually do not attack humans.

Reproduction Unlike most other reptiles, crocodiles andalligators care for their eggs and newly hatched young. Afterlaying eggs, the female stays near the nest. From time to time,she comes out of the water and crawls over the nest to keep itmoist. After the tiny alligators or crocodiles hatch, the femalescoops them up in her huge mouth. She carries them from thenest to a nursery area in the water where they will be safer. Foras long as a year, she will stay near her young until they canfeed and protect themselves.

When do alligators and crocodiles hunt?

FIGURE 23Alligator and Crocodile Alligators and crocodiles are the largest reptiles still living on earth. They are similar in many ways, including appearance. Comparing and Contrasting How can you tell the difference between an alligator and a crocodile?

Video PreviewVideo Field TripVideo Assessment

Fishes, Amphibians, and Reptiles

Alligator Crocodile

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Turtle Breathing

Materials

live turtle, such as a box turtle

Time

5 minutes

Focus

Challenge students to consider adaptations turtles have for breathing within the confines of a shell.

Teach

Ask:

How does your chest move when you breathe?

(In and out)

If the turtle’s chest moves like yours does, does its shell get in the way?

(Yes)

Allow students to carefully observe the turtle as it breathes. Students should notice that the exposed soft tissue around the turtle’s forelimbs and hind limbs moves.

Apply

Ask:

What replaces the in-and-out motion of chests of vertebrates without shells?

(The front-and-back motion of tissue around limbs)

learning modality: visual

L1

Math Skill

Making and interpreting graphs

Focus

Compare bar graphs to determine the effect of incubation temperature on the sex of baby alligators.

Teach

Make sure students understand that the answer to Question 2 is based on the ratio of males to females in the groups of eggs, not the absolute number.

Answers

1.

29.4

°

C

2.

The warmer the incubation temperature, the greater the proportion of males.

3.

According to the graph, out of the 50 alligators that were incubated at 31.7°C, 40 (or 80%) were males. So, I would expect 80% of 100 eggs (80) to hatch as males.

Monitor Progress L2

Writing

Have students compare the beaks of leatherback sea turtles with the teeth of alligators and crocodiles. Have them tell how each adaptation contributes to the animals’ ability to successfully acquire food. Students can save their paragraphs in their portfolios.

Answers

Figure 23

An alligator has a broad rounded snout, and few of its teeth are visible when its mouth is shut. A crocodile has a pointed snout, and most of its teeth are visible when its mouth is shut.

They hunt at night, hiddenfrom prey.

Tortoises

TurtlesTurtles live in the ocean, in fresh water, and on land. Turtlesthat live on land are commonly called “tortoises.” A turtle is areptile whose body is covered by a protective shell thatincludes the ribs and the backbone. The bony plates of theshell are covered by large scales made from the same materialas the skin’s scales. Some turtles have shells that are largeenough to cover the whole body. A box turtle, for example, candraw its head, legs, and tail inside its shell for protection. Otherturtles, like the snapping turtle, have much smaller shells. Tur-tle shells may be hard or as soft as pancakes.

Turtles feed in a variety of ways, but all have a sharp-edgedbeak instead of teeth for tearing food. Some turtles are carni-vores, such as the largest turtles, the leatherbacks. Leatherbacksfeed mainly on jellyfishes. Their tough skin protects them fromthe effects of the stinging cells. Other turtles, such as theGalápagos tortoise, are herbivores. They feed mainly oncacti, using their beaks to scrape off the pricklyspines before swallowing the cactus.

What are turtles that live on land called?

The Sex Ratio of Newly Hatched AlligatorsThe temperature of the developing eggs of the American alligator affects the sex ratio of the young. ( Sex ratio is the number of females compared with the number of males.) The graph on the right shows the numbers of young of each sex that hatched from eggs in which the young developed at different temperatures.

1. Reading Graphs At which temperature(s) did only females hatch?

2. Drawing Conclusions What effect does the temperature of developing eggs have on the sex of the baby alligators?

3. Calculating If 100 eggs developed at 31.7°C, about how many of the young would be male?

FIGURE 24A Galápagos Tortoise The Galápagos tortoise lives on land, where it eats mainly cacti.

Sex Ratio of Newly Hatched Alligators

Nu

mb

er o

f Yo

un

g

Temperature of Developing Eggs (ºC)

120

100

80

60

40

20

030.629.4 31.7 32.8

FemalesMales

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Extinct Reptiles—The Dinosaurs

Teach Key ConceptsInvestigating DinosaursFocus Review with students the meaning of the term extinct.

Teach Explain that before dinosaurs died out 65 million years ago, they occupied many of the habitats and played many of the roles of modern vertebrates. Ask: What type of vertebrates are dinosaurs? (Reptiles)

Apply Ask: How were dinosaurs unlike modern reptiles? (Some were much larger; they might have been endothermic) learning modality: verbal

L2

Monitor Progress L2

AnswersFigure 25 The long neck may have allowed Brachiosaurus, who was an herbivore, to reach the leaves on tall trees.

Tyrannosaurus rex

Assess

Reviewing Key Concepts1. a. Reptiles are ectothermic vertebrates with scaly skin that lay their eggs on land. b. Dry, scaly skin; amniotic egg; kidneys that concentrate urine c. It would dry out.2. a. Lizards and snakes, alligators and crocodiles, turtles b. Lizards c. Alligators are carnivores that hunt at night, swimming rapidly towards prey and clamping down on prey with their huge, muscular jaws. Turtles are either herbivores or carnivores that use their beaks to scrape and tear their food.3. a. 65 million years ago b. Brachiosaurus, like other dinosaurs, had legs positioned directly under its body, which allowed it to move more easily than other reptiles. c. They could have been more active at night and in colder climates.

ReteachCall on students to describe the features of one of the three main groups of reptiles.

Teaching Resources

• Section Summary: Reptiles• Review and Reinforce: Reptiles• Enrich: Reptiles

L1Keep Students on Track Check that students have chosen appropriate and safe materials for building their reptile model. Be sure that students are modeling the same adaptation in all three models.

Writing Mode Exposition How-To

Scoring Rubric 4 Includes an accurate, detailed description; writing is clear3 Includes accurate description; clear writing2 Includes accurate description; unclear writing1 Description is inaccurate and unclear

Extinct Reptiles—The DinosaursMillions of years ago, huge turtles and fish-eating reptilesswam in the oceans. Flying reptiles soared through theskies. Snakes and lizards basked on warm rocks. And therewere dinosaurs of every description. Unlike today’s rep-tiles, some dinosaurs may have been endothermic. Somedinosaurs, such as Brachiosaurus in Figure 25, were thelargest land animals that ever lived.

Dinosaurs were the earliest vertebrates that had legspositioned directly beneath their bodies. This adaptationallowed them to move more easily than animals such assalamanders and lizards, whose legs stick out from thesides of their bodies. Most herbivorous dinosaurs, such asBrachiosaurus, walked on four legs. Most carnivores, suchas the huge Tyrannosaurus rex, ran on two legs.

Dinosaurs became extinct, or disappeared from Earth,about 65 million years ago. No one is certain why. Today,it’s only in movies that dinosaurs shake the ground withtheir footsteps. But the descendants of dinosaurs may stillexist. Some biologists think that birds descended from cer-tain small dinosaurs.

Give an example of a dinosaur that ran on two legs.

FIGURE 25Brachiosaurus Brachiosaurus grew to be more than 22.5 meters long—longer than two school buses put together end to end. Inferring What advantage did a long neck give Brachiosaurus?

Section 4 Assessment

Target Reading Skill Identifying Main Ideas Use the information in your graphic organizer to help you answer Question 1 below.

Reviewing Key Concepts1. a. Defining What is a reptile?

b. Explaining What are three adaptations that allow reptiles to survive on land?

c. Predicting What might happen to a reptile egg if part of its shell were removed?

2. a. Identifying What are the three main groups of reptiles?

b. Classifying A gecko is a small reptile that has no shell protecting its body. It uses its legs to climb trees. Into which reptile group would you classify the gecko?

c. Comparing and Contrasting Compare and contrast how alligators and turtles obtain food.

3. a. Reviewing When did the dinosaurs become extinct?

b. Interpreting Diagrams What adaptation did the dinosaur in Figure 25 have that helped it survive?

c. Inferring What advantage might a dinosaur that was an endotherm have had over other reptiles?

Product Label Write a “packaging label” that will be pasted onto the eggshell of a reptile. Include on your label a list of the contents of the shell and a one-paragraph description of the egg’s ability to survive in a dry environment.

4

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