ArthropodsInsects, Spiders, & Crustaceans

Unit Study for Grades K - 6

© Jenny Phillips2

ARTHROPODSInsects, Spiders, and Crustaceans

Table of Contents

Lesson 1 - Introduction to Arthropods 1

Lesson 2 - Introduction to Insects 12

Lesson 3 - Oral Presentations 17

Lesson 4 - Insect Stations: Mosquitoes, Fireflies Termites, Silkworms 18

Lesson 5 - Bees and Wasps: Part 1 29

Lesson 6 - Bees and Wasps: Part 2 32

Lesson 7 - Entomologist Jean-Henri Fabre 37

Lesson 8 - Butterflies: Part 1 40

Lesson 9 - Butterflies: Part 2 45

Lesson 10 - Ants 49

Lesson 11 - Insect Defenses 55

Lesson 12 - Arachnids 58

Lesson 13 - Crustaceans 61

Created by Jenny Phillips, Mary Beyer, and Lezlie-Ann Ivie

Insects, Spiders, and CrustaceansARTHROPODS

©2016 Jenny Phillips | www.Jennyphillips .com

No part of this PDF document may be copied or reproduced for those outside your family or school group.

Science JournalAll of The Good & the Beau ful science units include ac vi es for a science journal. For each child, prepare a 1” to 2” 3-ring binder to func on as their science journal. Tabbed divider pages can be used to separate science units. Also, have wide-ruled paper and blank white paper on hand for science journal ac vi es. All completed journal ac vi es are to be kept in the science binder. You may also consider having children create a cover for their science journals, which they insert under the clear cover of the binder.

Science WallAll of The Good & the Beau ful science units include vocabulary words to be placed on your science wall, which is a wall in your learning area on which you can a ach the vocabulary words and other images. Print and cut out the vocabulary word cards at the beginning of the unit. The course will indicate when to place them on the wall.

Lesson Mini BooksMany of the lessons included in this unit incorporate science mini books. The mini books are included with the lesson and require very li le assembly. To make your mini books, simply print the pages

single-sided, cut them in half along the do ed lines, stack the pages together, and staple twice along the le side.

Lesson Prepara onAll of the Good & Beau ful science units include easy- to-follow lesson prepara on direc ons at the beginning of each lesson.

Teaching Older Children?This unit study is designed for Grades K-6. If you are teaching older children (Grades 7-12), look for the “older children” symbol (a magnifying glass) at the end of most lessons. There you will fi nd ideas for guiding older children through more in-depth research and study.

You also may consider having older children read The Secret Lives of Backyard Bugs by Judy Burris and Wayn Richards. This book, one of the few on the subject that does not reference evolu on, will help older children to dig deeper into topics studied in this unit.

You also may consider having older children (grades 9+) read The Life of the Spider by Jean-Henri Fabre. Fabre was a famous entomologist and man of faith that you will study in this unit. The book is engaging, well-wri en, and challenging.

Unit Information

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Lesson 1None

Lesson 2None

Lesson 3None

Lesson 4• Brown clay (any kind)• Glow s cks (one per child)

• A small piece of silk material (op onal)

Lesson 5

• Paper towels

• Scissors

• A handful of Cheetos

• A candy or snack (e.g. fruit snack or grape)

• 1/8 teaspoon of honey

• One sesame seed for each child

Lesson 6• Several co on balls• A few diff erent scents to put on the co on balls,

such as peppermint, vanilla, almond, dish soap, lemon, or cinnamon

Lesson 7None

Lesson 8None

Lesson 9None

Lesson 10 • An ant farm

Lesson 11None

Lesson 12• Scotch tape• A few drops of vegetable or olive oil

Lesson 13 • Op onal: A crayfi sh dissec on kit

Insects, Spiders, and CrustaceansARTHROPODS

Supplies Needed

Lesson 1Science

Objec ve

• Help children understand the dis nguishing characteris cs of arthropods and the diff erence between insects and arachnids.

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Prepara on:

Make sure each child has a science journal for this lesson and all upcoming lessons.

Supplies needed:

None

Lesson 1 - Introduction to Arthropods

Read to children:Have you ever considered how full of life our world is? Do you know what a square mile is? [a piece of land equal to a square that measures one mile on each side] There 15 mes more insects in one square mile of an empty fi eld than there are people in the United States. Imagine this—if we were to fi nd all the insects within a square mile of a fi eld, we would fi nd more than fi ve billion insects. How many insects do you think are living in our backyard?

Insects and spiders are so small that we o en pass by them, but they are everywhere. As we pass over plain and valley and mountain, we fi nd insects big and small, some hidden in the moss or the thick grass, rolled up in the leaves, boring into the stems and trunks of trees, ea ng their way underground. But they form three-fourths of the whole animal kingdom. God created over 950,000 types of insects and spiders, and they are so interes ng to study, and do us so much good and so much harm that we should know about them.

Insects and spiders are classifi ed in the animal kingdom named arthropods. About 85% of all the animals we know in the world are arthropods. This kingdom includes insects, arachnids (spiders) myriapods (cen pedes and millipedes), and crustaceans (creatures like crabs and lobsters).

Ac vity: Insect Vocabulary

Place the vocabulary words on the wall. As you go over each word, read and discuss the following informa on with children. Consider having older children

read some of the informa on out loud. Then, place the vocabulary words and defi ni ons on your science wall.

InvertebratesThere are two basic groups of higher animals. They are vertebrates and invertebrates. Invertebrates are animals that do not have backbones.

Mammals (such as bears and monkeys), amphibians (such as frogs and toads), rep les (such as turtles and snakes), fi sh, and birds all have vertebrae (backbones). That might seem like a lot of animals, but all of these types of animals make up less than 4% of all animal species. That means that 96% of animal species are invertebrates and do not have backbones. The largest invertebrate is a huge squid that can grow to over 40 feet long and weigh over 1,000 pounds. The smallest invertebrates are so small that you cannot see them without a microscope.

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Science Lesson 1

Science Journal: Have children write and illustrate the defi ni on for “invertebrates” in their science journals. Also, using the following chart, have children make a chart in their science notebooks showing some animals that are vertebrates and some animals that are not invertebrates. Younger children can create a simplifi ed chart by just drawing some pictures under each heading.

InvertebratesAnimals without a Backbone or

Spinal Column

VertebratesAnimals with a Backbone or Spinal

Column

Sponges Fish

Coelenterates Amphibians

Echinoderms Reptiles

Worms Birds

Mollusks Mammals

ArthropodsWhich include insects, arachnids (spiders and their relatives), and crustaceans (crab,

lobster, etc.)

ExoskeletonAn exoskeleton is a hard covering that supports and protects the bodies of some type of animals. Many invertebrates, or animals without backbones, have exoskeletons. Exoskeletons are on the outside of the body.

Science Journal: Have children write and illustrate the defi ni on for “exoskeleton” in their science journals.

Exoskeleton

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Science Lesson 1

Cold BloodedYou are warm-blooded. That means your body controls its temperature. Birds and mammals are also warm blooded. But arthropods are cold blooded. A cold-blooded animal cannot maintain a constant body temperature. The term cold-blooded might lead you to believe that a cold-blooded animal would be cold all the me, but that is not the case.

The temperature of a cold-blooded body is determined by the outside surroundings. Cold-blooded animals will move around during the day between the shade and the sun to warm up or cool down. Cold-blooded animals are much more ac ve in warm environments and are very sluggish in cold environments. Some insects die when it gets too cold. Some survive cold weather by moving underground or migra ng to warmer areas in the winter. Honeybees stay warm by crowding together and genera ng heat by moving their wings.

Science Journal: Have children write and illustrate the defi ni on for “cold-blooded” in their science journals.

Read to children:

Let’s study how spiders (arachnids) and insects are diff erent. To do this, you will create a Venn diagram in your science notebook. Spiders have eight legs, but insects have only six legs. Spiders have two dis nct body parts; insects have three dis nct body parts. Also, all spiders can make silk threads, but insects cannot. We already know some of the ways that insects and spiders are the same: they are both cold blooded, they both have exoskeletons, they are both invertebrates.

Older Children - Lesson Extension

Have older children (Grades 7-12) complete the following:

• Research the following terms online and take notes (and draw illustra ons where applicable) in their science notebooks: MANDIBLES | TRACHEAL RESPIRATORY SYSTEM | ECDYSIS

• Research and write about the diff erence between a cen pede and a millipede.

insects arachnids

• have six legs• have three

body parts• cannot make

silk threads

• are cold-blooded

• have exoskeletons

• are invertebrates

• have eight legs

• have two body parts

• can make silk threads

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Science Lesson 2

Worksheet: Insects

Have children complete the workshop by copying the answers from the KEY.

Science Journal: Have children draw or trace the ant below in their science journal and label the parts.

Parts of an Insect

head thorax abdomen

antenna

Insects

Butterfl ies

Beetles

Dragonfl ies and Ants

Flies

Ladybugs

Grass hoppers

Bees

Moths

Mosq

uitoes

© Jenny Phillips

© Jenny Phillips

Butterfl ies

Beetles

Dragonfl ies and Ants

Flies

Ladybugs

Grass hoppers

Bees

Moths

Mosq

uitoes

Insects have six legs.The body of insects is made of three parts.

Insects have antennae. Most insects have two pairs of wings.

Insects are cold-blooded. Insects lay eggs.

Insects have exoskeletons.

KEY Insects

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Science Lesson 4

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Science Lesson 4

• How many times per second does a mosquito beat its wings? [300-600]

• True or false: only female mosquitoes suck blood. [true—Female mosquitoes usually eat nectar. They only suck blood when they need the protein from blood to make eggs.]

• How much blood can a mosquito suck up? [more than three times its weight]

Mosquito Trivia Cards

• What is Malaria? [a potentially deadly disease found mainly in Africa and South Africa that is carried by mosquitoes; over 1 million people die from Malaria each year]

• Are mosquitoes the only known species that carry Malaria? [yes]

• True or false: mosquitoes prefer the blood of animals over humans. [true]

• Where do mosquitoes lay their eggs? [in or near water]

• Is there anything good about mosquitoes? [Yes--they provide food for creatures such as birds, dragonflies, and frogs]

• What do male mosquitoes eat? [nectar from plants]

• True or false: sweat attracts mosquitoes. [true]

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Science Lesson 4

Firefly Images

Pho nus pyralis, a species of fi refl y found in the eastern United States (Terry Priest / wikimedia commons)

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Science Lesson 4

Firefl iesby Jennifer D. Lerud

Firefl ies In The Garden

by Robert Frost, published in 1928

Here come real stars to fi ll the upper skies,

And here on earth come emula ng fl ies,

That though they never equal stars in size,

(And they were never really stars at heart)

Achieve at mes a very star-like start.

Only, of course, they can’t sustain the part.

Have you ever seen a fi refl y? The famous poet Robert Frost hasn’t been the only one to get excited at seeing their li le twinkling lights among the trees on a warm summer night. Firefl ies are many people’s favorite insects. Not everyone calls them fi refl ies, however. Some people call them lightning bugs. But no ma er what you call them, they are really winged beetles, not fl ies at all!

There are about 2000 species of fi refl ies, and they are found in temperate and tropical climates. Marshes and wet, wooded areas give their babies, called larvae, plenty of food. Water is really important for some fi refl y larvae, because they live underwater and have gills before climbing up onto land to become adults. Some species don’t fl y, though most of them do. Some mes it’s only the females who don’t fl y. They have so bodies like the larvae. Only their compound eyes show the diff erence between them.

Some fi refl ies are only awake at night. They’re called nocturnal. Some are awake during the day. They’re called diurnal.

And when they fl y and light up, it’s an amazing sight! They are using chemicals in their lower abdomens to fl ash signals to each other, telling each other what species they are. That’s called biolu-minescence. Almost 100 percent of this chemical reac on goes into making light, unlike 10 percent for an incandescent light bulb. Each species has its own dis nct pa ern of fl ashes. That way, they know they’re going to fall in love with the right type of fi refl y.

Firefl ies like to eat meat. Most of the larvae grow underground, which is why people in Europe call them glowworms, and they eat slugs, worms, and snails. The water larvae with gills like to eat aqua c snails. Once they grow into adults, they might eat other fi refl ies, but most eat pollen and nectar, and some don’t eat anything at all. That’s because they have very short lives.

Rising up from deserts, tropical rain forests, temperate woodlands, and possibly . . . your local park, termite mounds are found on almost every con nent. These mounds can stretch to 80 feet across and 30 feet high—taller than a two-story house! They are very strong

structures made from mud, digested wood, saliva, and feces.

Termites

1

The only problem is, termites can cause a lot of destruc on when they live by humans. Homes and objects made with wood can be destroyed quickly by termites. They are known as “silent

destroyers” because they can chew through walls and fl oors without being detected un l much damage is done. Each year, termites cause billions of dollars in damage to buildings.

Termites are busy li le creatures. They never stop ea ng or working. They eat 24 hours a day, seven days a week! Can you imagine working every hour of every day with no rest?

There are so many termites spread across the con nents that the total weight of all the termites in the world is many mes more than the total weight of all the humans in the world. But it is a good thing

that we have so many termites in our world, because they play an important role in decomposing huge amounts of decaying wood and plants. Without termites, our world would be a lot messier.

4

3

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Science Lesson 8

Objec ve

• Help children gain knowledge about bu erfl ies and scien fi c names.

Prepara on:

Print out the pages with the bu erfl ies and the scien fi c and common names of the bu erfl ies. Then cut out all the boxes.

Print out the worksheet tled “Exploring the World Bu erfl y Census.” (one for each child)

Lesson 8 - Butterflies: Part 1

Ac vity: Give children 10 minutes to draw and color bu erfl ies of their own design. Ask children to make the bu erfl ies very detailed and to try to make the pa erns and colors on the right set of wings match the pa erns and colors on the le set of wings.

Read to children:How many diff erent bu erfl ies were you able to design in 10 minutes? Pause for answers. In 2007, Adrian Hoskins collected and combined data from diff erent sources and produced a World Bu erfl y Census which lists 17,657 currently known species of bu erfl ies in the world. But more species of bu erfl ies are being discovered every year.

It is amazing to think about God designing all of those diff erent bu erfl ies. Imagine drawing 10 diff erent designs for bu erfl ies every day. It would take you almost fi ve years just to draw every known species in the world today. God truly designed a very diverse and interes ng world for us to live on.

Explore with children the World Bu erfl y Census at h p://www.learnaboutbu er-fl ies.com/World%20Census.htm

Have children complete the worksheet tled “Exploring the World Bu erfl y Census.”

Read to children:Jean-Henri Fabre, whom we learned about in the last lesson, wrote this about bu erfl ies:

Oh, how beau ful! Oh, my goodness, how beau ful they are! There are some whose wings are barred with red on a garnet back-ground; some bright blue with black circles; others are sulfur-yellow with orange spots; again others are white fringed with gold-color. They have on the forehead two fi ne horns, two antenna, some mes fringed, some mes cut off like a tu of feathers. Under the head they have a proboscis, a sucker as fi ne as a hair and twisted into a spiral. When they approach a fl ower, they untwist the proboscis and plunge it to the bo om of the corolla to drink a drop of honeyed liquor. Oh, how beau ful they are! Oh, my goodness, how beau ful they are!

Read to children:Scien sts throughout the world use a common system for naming insects (and all other living organisms). Thus, scien fi c names are the same in every place and in every language.

In this system, two words are used. The fi rst word indicates the “genus” (a subfamily) to which the species is assigned. The fi rst word is always a

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Science Lesson 8

capitalized La n name. The second name is the specifi c name and is not capitalized.

Since La n names can be long and hard to pronounce, common names are given to insects as well, so people can talk about insects in non-scien fi c language.

Ac vity: Lay out the pictures of the bu erfl ies (numbered 1-6) and the scien fi c and common names that you cut out. Have children try to match up the bu erfl ies with their scien fi c and common names. They are given here for your reference.

#1:

Scien fi c Name: Danaus plexippusCommon Name: Monarch

#2:

Scien fi c Name: Aglais ioCommon Name: Peacock

#3

Scien fi c Name: Apatura irisCommon Name: Purple Emperor

#4

Scien fi c Name: Vanessa virginiensisCommon Name: American Painted Lady

#5

Scien fi c Name: Celastrina argiolusCommon Name: Holly Blue

#6

Scien fi c Name: Pararge aegeria

Common Name: Speckled Wood

Science Journal: Have children read the facts about bu erfl ies on this page. In their science journals, have children make a list of the facts they think are most interes ng.

• Bu erfl ies have four wings.

• Most bu erfl ies feed on nectar from fl owers.

• Bu erfl ies can’t hear, but they can feel vibra ons.

• Bu erfl ies taste with their feet.

• Bu erfl ies use two antennae on top of their heads to see, smell, and feel.

• Once it emerges from its chrysalis as an adult, a bu erfl y only lives 2-4 weeks.

• Bu erfl ies can only fl y if they are warm enough. Thus, you will o en see bu erfl ies basking in the sun with their wings spread open.

• Like all insects, bu erfl ies are cold-blooded. Thus, outside condi ons determine a bu erfl y’s body temperature. To keep the temperature adjusted correctly, bu erfl ies will overlap or angle their wings to adjust the amount of the wing exposed to the sun. The veins located on the wings carry heat to the body. Bu erfl ies must seek shade when temperatures get too hot.

• A bu erfl y’s mouth is along tube called a proboscis through which it sucks the sweet nectar from fl owers. When the bu erfl y does not want to eat, it rolls the tube up! It can only drink; it cannot chew.

• Bu erfl ies drink from mud puddles, which are rich in the minerals and salts they need to survive.

• Bu erfl ies don’t have lungs.

• Bu erfl ies breath through openings on their abdomen called spiracles.

• Bu erfl ies cannot see all of the colors humans can see, but they see a range of ultraviolet colors invisible to the human eye.

• Bu erfl ies are the second largest group of pollinators.

Quiz children on the facts listed in the bulleted list above.

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Science Lesson 8

#1 #2

#3 #4

#5 #6

© Jenny Phillips

1. Draw three bu erfl ies on the con nent which has the most species of bu erfl ies.

2. Draw one bu erfl y on the con nent with the least species of bu erfl ies.

Exploring the

World Butterfly Census

1. What is the name of the largest family of bu erfl ies?

_____________________________________________________________________________________

2. Why do you think there are no bu erfl ies listed in the arc c region?

_____________________________________________________________________________________

3. Using the World Bu erfl y Census and the chart below, answer the following ques ons.

Are there more species of ants or bu erfl ies?___________________________

Are there more species of beetles or bu erfl ies?_________________________

Are there more species of mosquitoes or bu erfl ies?_____________________

Number of species

ants: 12,000

beetles: 350,000

mosquitoes: 3,500

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Science Lesson 9

Objec ve

• Teach children about the life cycle of a bu erfl y, Monarch migra on, and bu erfl ies in your area.

Prepara on:

Print out the chart “The Life Cycle of a Bu erfl y” or have it ready to display on a computer or tablet.

Print out a blank bu erfl y life cycle sheet for each child.

Select and be ready to play one of the videos suggested in the lesson.

Lesson 9 - Butterflies: Part 2

Complete the following:

1. Show children the chart in this lesson tled “The Life Cycle of a Bu erfl y,” and tell them you are going to study the life cycle of a bu erfl y.

2. Give each child a copy of the blank chart. Have them write “The Life Cycle of a Bu erfl y” in the top box.

3. Have children illustrate and label the fi rst stage, “eggs,” while you read the following:

Bu erfl ies and moths undergo a complete metamorphosis in which they go through four diff erent life stages. These four stages can take one month to one year to complete, depending on the type of bu erfl y.

A bu erfl y starts its life as an egg a ached to a leaf or stem of the type of plant its species likes to eat.

4. Have children illustrate and label the second stage, “caterpillar,” while you read the following:

When the larva (caterpillar) hatches from an egg, it is a ny worm-like creature that is very hungry! It eats

leaves or fl owers almost constantly, star ng with the leaf on which it was born. Because caterpillars eat so much, they grow fast. In fact, they grow so fast that they outgrow their skin because it does not stretch or grow. Caterpillars shed their skin several mes while they are growing, and then get new skin. This is called mol ng.

Photo by Andy Potter

Ants are almost everywhere in our world; they live on every con nent. Over 12,000 diff erent species of ants have been classifi ed, but scien sts believe there are at least 10,000 species

of ants yet to be discovered. Ants especially like tropical forests where they some mes make up half of the insects in the area.

Ants

1

Ants are usually black or red or both, but some species are metallic or green. They can li 20 mes their own body weight. If you could li a horse above your head and carry it, you would

be about as strong as an ant. Ants are also one of the smartest types of insects. They typically eat nectar, small insects, or seeds. However, some species, such as army ants, prey on birds,

rep les, or even small mammals.

Ants are social insects; they live in groups and work together. Ants build their colonies inside trees, underground, or in mounds. Some colonies have only a few dozen ants; others have millions.

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PPPPPPPhhhhooooooottttttttttoooooooo bbbbbbbbbbbbyyy DDDDDDDDooouuuuggggggg BBBBBBBBBBBBBBBeeeeeeeeeccccccccckkkkkkkkeeeeeeeerrrrrrrsssssssss

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Science Lesson 11

Objec ve

• Help children learn about how insects use defense mechanisms to protect themselves.

Prepara on:

Op onal: Set up a tablet, computer, or other device on which children can watch one of the suggested videos listed in this lesson.

Lesson 11 - Insect Defenses

Read to children:As humans, we have many body processes, charac-teris cs, and tools we can use to protect us from harm. For example, our eyelashes protect things from ge ng into our eyes, our skin protects us against bacteria so we don’t get sick too easily, and we can also wear shoes to protect our feet. Insects also have characteris cs they use to protect themselves; they are called defense mechanisms. Diff erent kinds of insects use diff erent mechanisms to protect themselves against predators and a ackers.

Science Journal: Have the children pull out their science journals. At the top of a page write, “Insect Defense Mechanisms.” Then, have children list (and/or illustrate) the diff erent defense mechanisms that are specifi ed in each of the following paragraphs as you read and discuss them.

Read to children:Take a look at this katydid.

What characteris cs do you think this insect can use to protect itself? Pause for responses. This Katydid uses a defense mechanism called camoufl age, which allows the insect to blend in with its surroundings so that its presence is hid or disguised.

Look at this next picture. How many insects can you fi nd? Pause for responses.

Look how the two insects look almost exactly like the branch that is next to them. This defense mechanism is similar to camoufl age, but instead of blending in and hiding with the same colors, it hides by resembling similar items that are in their habitat. This defense mechanism is called mimesis. The katydid we just looked at also uses mimesis because its shape and coloring looks like its surroundings, so it can blend in and hide even if it is not si ng directly on a leaf.

Another defense mechanism is called repellency. Repellency is when insects give off s nky smells. The s nk bug has its name because of the defense

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Science Lesson 13

Objec ve

• Help students understand the dis nguishing features of crustaceans and explore these fascina ng creatures.

Prepara on:

Print out the sheet “Parts of a Crayfi sh.” (one for each child)

Print out and assemble the mini book “Crustaceans.”

Supplies needed:

• Op onal: crayfi sh dissec on kit

Lesson 13 - Crustaceans

Ac vity: Insect Vocabulary

Place the following vocabulary words on the wall as you discuss the words and their defi ni ons: CRUSTACEANS and MOLTING.

Read the mini book Crustaceans included in this lesson.

Science Journal: Give each child a copy of the sheet "Parts of a Crayfi sh." Read the informa on about each body part below as children fi ll out their sheet. Have children place the sheets in their science notebooks.

Antennae: These are sensory organs that func on to help the crayfi sh hear, smell, and taste. Crayfi sh have two sets of antennae.

Compound Eyes: Crayfi sh eyes are diff erent from human eyes. Not only do crayfi sh have compound eyes, but they s ck out on the end of stalks, allowing them to detect fast movement.

Walking Legs: Crayfi sh have four pairs of walking legs. They are used primarily for walking and gathering food.

Claws: Crayfi sh use their claws to catch food, for defense, and for moving small items such as pebbles.

A major diff erence between diff erent species of crayfi sh are the size and shape of their claws. Some are long and skinny; some are very short and wide, and some are weak, and almost nonexistent.

Thorax: The head and the thorax together are called the cephalothorax. The cephalothorax is covered by a thick armor called a carapace.

Abdomen: The abdomen is made of 7 jointed sec ons. The last sec on is like a fi n and is called the telson. Underneath the abdomen are fi ve pairs of appendages called swimmerets. They are mainly used as swimming legs, but they can also catch food.

Op onal Ac vity: Crayfi sh Dissec onIf desired, complete a crayfi sh dissec on. A crayfi sh dissec on kit with instruc ons can be purchased on Amazon.com or other websites.

Older Children - Lesson ExtensionHave older children (Grades 7-12) complete the following:

• Write a paper that compares the mol ng process of three diff erent species of arthropods.

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antennaeused for hear, smell, and taste

compound eyeseyes are mounted on stalks called PEDICLES

walking legs

Clawsused for hear, smell, and taste

head thoraxfused to the head

abdomen7 joined sections

Parts of a Crayfi shKEY

Within the arthropod phylum of the animal kingdom is a group of animals that may look like large insects. Just like insects, this type of animal has an exoskeleton (a hard, shell-like

coverings that protects the so body parts from being crushed or injured) and jointed legs (used for walking and picking up food). However, unlike insects, instead of only one pair of antennae (used for feeling, tas ng, and smelling), they have two pair!! These animals are

called crustaceans. 1

Crustaceans

6

5

Did you know that you don’t have to be anywhere near the water to see one special type of crustacean? You might even be able to see them in your own yard! If you go on a spring me walk, you may see these li le gray or brown crustaceans, with their seven pairs of legs and two pairs of antennae, crossing your path. You also might fi nd them if you turn over a rock while you’re gardening. But if you frighten them or try to pick them up, they will roll up into a ball to protect them-selves. Have you guessed that we are talking about roly-poly bugs? Also called pill bugs, sow bugs, and potato bugs, roly-poly bugs are ny crustaceans that live on land. Their hard

exoskeleton consists of overlapping plates that allow them to curl up and roll when they feel threatened. Their dull color also enables them to blend in and hide from predators.

One type of crustacean is a fairly common pet: the hermit crab. Hermit crabs are unique be-cause they can’t make their own shells; they must hide in shells le behind by other animals. As they grow, hermit crabs con nue to look for bigger and be er fi ng shells. There are over 600 types of hermit crabs.