In this unit, students learn how to classify and identify arthropods.Students examine the similarites and differences between creatureswith which they are familiar in order to develop an understanding ofarthropod classification. They will use the seven major categores ofclassification (Kingdom, Phylum, Class, Order, Family and Genus).

Biodivesity, Scientific Classification (Kingdom, Phylum, Class, Order,Family and Genus), Plants, Adaptation, Ecosystems, GrowingSeasons, Models, Organisms.

Use physical characteristics of various plant specimens to classifythem.

Identify rules for classification of plants. Apply seven major cate-gories of classification.

Determine the reasons why scientists classify plants and animals.

Determine relationships between plants and their local ecosys-tems—considering growing seasons, rainfall, temperatures, othercreatures in the system and other critical elements they identify.

Demonstrate understanding of major concepts with final portfolioproject.

This timeline offers a day-by-day plan forusing all the components in the unit, includingsuggestions for supplementary readings, dis-cussion questions, homework assignments andreadings for further study. Assessment strate-gies include portfolio assessment and day-to-day accountability for students working bothindividually and in small groups.

Prepare Your Investigation: Identification &ClassificationStudents use their prior knowledge of classifi-cation to frame their investigation of scientificclassification systems. They learn seven majorcategories of classification (Kingdom, Phylum,Class, Order, Family, Genus, Species) andapply those categories to organisms whosecommon names they know.

Research on the Web: Identify & ClassifyInsectsStudents conduct Web research to examinecommon and scientific names, images anddescriptions of insects in every insect order.They investigate a classification key (includingimages of insects, once identified) for insectsthat feed on tomato plants. In the process, theylearn about how scientists identify insectsusing a classification key.

Classroom Activity: Name That CritterStudents work cooperatively to investigate agroup of "mystery creatures" in order to discov-er the shared characteristics of arthropods.They may then use their discoveries to createmystery entries for a jeopardy game in whichteams compete to identify arthropods.

Classroom Activity: Arthropod JeopardyStudents use their research on arthropods todesign questions for a class Jeopardy game.This activity can be adapted for use with anyunit in the Explore Biodiversity curriculum.

C E N T E R F O R B I O D I V E R S IT Y A N D C O N S E R -VAT IO N R EA DI N G S

http://research.amnh.org/biodiversity/center/newsletter/webletter.html

" What's the Buzz? The Bee Workshop at theS o u t hwestern Research Station." Spring, 20 0 0 .

"The Invertebrate Laboratory: Bugs UnderGlass." Fall, 1999.

"The Little Known World Underfoot."Summer, 1999.

"Butterfly and Moth Workshop." Fall, 1998.

I N T E R V IE W W I T H S C I E N T IS T S

Profile: Barrett KleinBarrett Klein, a display maker at the Am e r i c a nMuseum of Natural History (AMNH), describeshis path to entomology, which began with a loveof art.

Profile: Sally GoodmanSally Goodman, Curatorial Assistant at theAMNH, describes her discovery that her artisticskills could find a place in the Museum'sEntomology Department.

Profile: Eric QuinterEric Quinter, Senior Scientific Assistant inAMNH's Entomology Department, describesthe influence of his countryside boyhood on hisdecision to become an entomologist. Quinterstresses the excitement of new discoveries, andthe possibility for even amateurs to discovernew species.

Profile: Kefyn CatleyKefyn Catley, National Science FoundationResearch Fellow at AMNH's EntomologyDepartment, describes his roundabout routeinto science after a long music career.

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A C T I V I T I E S

C O N T E N T R EA DI N G S“Arthropods at a Glance”This overview of arthropods includes a discussion of their physical fea-tures and a list of some of the more common arthropods.

S U P P L EM E N TA L R E F E R E N C E S : Ar t h r o p o d R e l a t e d We b S i t e s

www.insects.org/entophiles/index.htmThis site has great images of insects listed by order and includes a sec-tion of other arthropods.

http://ucmp.berkeley.edu/arthropoda/arthropoda.htm

http://ag.arizona.edu//tree/eukaryotes/animals/arthropoda/arthropo-da.htmTake a look at a tree that shows the relationships of all living things.

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This is a suggested timeline for the unit SoMany Kinds of Creatures: Learning toClassify. This timeline is designed for classeswith 45–55 minute-periods. The timeline usesall components in the unit; pick and choose tocustomize your unit if you wish. Suggestionsare made here for using the readings; you canalso give out the readings at the beginning ofthe unit, along with the portfolio sheet, and tellstudents that they are responsible for complet-ing the readings on their own time by the port-folio due date. If possible, return collectedgroup worksheets and other assignments theday after they are completed, or, in the case ofgroup work, on the next day that groups meet.

The unit, and each individual activity within it,is designed to encourage the development ofhabits of mind. Students not only learn howthe physical characteristics of arthropods caninform the ways in which they are classified;they also develop their skills in scientificinquiry by examining what they already knowto frame an investigation, developing hypothe-ses and designing tests for those hypotheses.Readings supplement hands-on investigations,and students record their observations andfindings in research journals before preparinga final project. This final project correspondsto the publication stage of scientific research.Suggestions for structuring this final projectare found on the student handout, Putting ItAll Together.

T I M E L I N E

Before you begin the unit, ask students to answer “Questions to Explore”from the first section of Prepare Your Investigation: Identification &Classification. This is an excellent homework assignment for the nightbefore or as an in-class activity before starting the unit. Ask students toread "What's the Buzz: The Bee Workshop at the Southwestern ResearchStation" and "The Invertebrate Laboratory: Bugs Under Glass" and writea response for each.

Each unit in the Explore Biodiversity curriculum includes cooperativelearning activities, some of which may be adjusted for individual work athome or in class. Keep in mind that many students do not yet know how towork effectively in groups. Spend some time discussing effective coopera-tive learning before you ask students to work cooperatively.

If you are using only one unit in the curriculum, begin the first day with awriting task that asks students to think about effective group work, e.g.:

When you are working with other students, what makes you want to par-ticipate? What makes you feel reluctant to participate? How do you help your teammates take part in discussion? What mightyou do that could make it difficult for others to participate?

Ask a few students to share their written responses in order to generate adiscussion of effective cooperative learning practices before starting thegroup activity.

If you are using more than one unit in the curriculum, you will not need torepeat this discussion with each new unit, though some or all of your stu-dents may need refresher discussions as you proceed. Substitute the follow-ing writing task to help your students prepare for the activity to come:

How do you know that a coat is a coat and a sweater is a sweater?

As students write, circulate and either collect homework (responses) or sim-ply mark that students have completed the assignment and reserve a moredetailed check for a journal collection date. Ask a few students to sharetheir writing responses. Use their ideas to open a discussion about the waywe classify things. Students then complete the second portion of PrepareYour Investigation: Identification & Classification.

After groups have completed the activity, gather together as a class. Createa class list of key classification concepts and terms.

HOME WORK : Read Profile: Barrett Klein and Profile: Sally Goodmanand write a response for each.

DAY 1: Prepare Your Inve s t i g a t i o n

B E F ORE DAY 1

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If all of your students have access to the Web, use Research on the Web:Identify & Classify Insects as an out-of-class assignment, with or withoutgroups/partners. If not, use class time for students to use the interactiveprogram. As you circulate, either collect homework (responses) or simplymark that students have completed the assignment and reserve a moredetailed check for the portfolio collection date.

Regroup as a class after the Web investigation to discuss the day's findingsand to generate a class list of findings.

HOME WORK : Read Profile: Eric Quinter and Profile: Kefyn Cateleyand write a response for each.

No t e: You may need to provide field guides, textbooks or other resourcesfor this activity. Decide in advance if you want students to depend on priorknowledge or to conduct research in order to complete Classroom Activity:Name That Critter. Make sure that your preparations don't give away thediscovery point of the activity, where students realize that shrimp and spi-ders and ants and crabs are all part of the same phylum.

Start the day with a short writing task:

How can you tell when two people are related?

As you circulate, either collect homework (responses/write-up) or simplymark that students have completed the assignment and reserve a moredetailed check for the portfolio collection date.

Have a few students share their writing responses. Discuss how we identifymembers of a family by their shared physical characteristics. (You mayeven want to talk about the dangers of classifying people by their physicalcharacteristics.) Then turn to the identification and classification of othercreatures and explain the day's activity. Distribute and discuss the handoutand distribute and resources you want students to use. Discuss your expec-tations before setting students to work.

Reserve time at the end of class for a discussion of the day's activity. Createa class definition of this group of creatures. Include some of the character-istics listed here, as well as other relevant information, such as habitats orinteractions with humans (including as food!), etc.

DAY 2: Research on the We b

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DAY 3: Classroom Ac t i v i t y

Arthropods have

segmented bodiespairs of jointed appendagesbilateral symmetrychitinous exoskeleton

HOME WORK : Read "Arthropods at a Glance" and write a response.

No t e: Classroom Activity: Arthropod Jeopardy requires that studentshave done some research on arthropods. Make sure that they have complet-ed ample research before completing the activity. You can accomplish thisby assigning readings/research in the days before the unit begins if you arenot completing this unit as part of a larger study of arthropods.

No t e: You can adapt Classroom Activity: Arthropod Jeopardy for use withany of the units in the Explore Biodiversity curriculum. It is a fun way toreview what students have learned and/or prepare for a final assessment.

To start class, ask students to complete the following prewriting task:

Describe an interesting feature of an arthropod.

Use your discussion as a segue into an explanation of the day's activity anddiscuss the criteria for a good question in the Jeopardy game.

Announce teams for Arthropod Jeopardy. Consider computer access in andout of class in deciding what materials to provide for groups. As you circu-late, either collect homework (journals) or simply mark that students havecompleted the assignment and reserve a more detailed check for a journalcollection date.

Reserve time at the end of the period for groups to discuss their process.Also provide a time to establish rule and clarify procedures (including timelimits) for the Jeopardy game. The activity defines a structure that allowsall students to participate in offering and answering questions. If youchoose to have students monitor the game, some students will not have thebenefit of investigating the questions. Consider asking students from anoth-er class to be moderators.

HOME WORK : Read "Butterfly and Moth Workshop" and write aresponse.

DAY 4: Classroom Ac t i v i t y

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Play Arthropod Jeopardy!

HOME WORK : Read "The Little Known World Underfoot" and write aresponse.

Ideally, you will be able to use a full class day to help students begin portfo-lio compilation and final projects. If not, use today's handout as a home-work assignment.

Begin class with a short writing task:

What have you learned about identifying and classifying arthropods? What further questions do you have about identifying and classifyingarthropods?

Ask a few students to share their responses. Use these responses as a segueinto a discussion of the portfolio. The self assessment will ask them to thinkfurther about what they learned during the unit. They will complete a finalproject and they can begin thinking about that today. Distribute and discussthe handout, Putting It All Together. Give students time to read throughthe handout and complete their responses. Then gather as a class to discussyour deadlines and expectations for projects and portfolios.

During the rest of the class period, students can begin compiling portfoliosand putting together ideas for their final projects. As you circulate, trou-bleshoot for individual students and discuss ideas with groups or with theclass. At the end of the period, have a few students share some of theirquestions or project ideas so that everyone can get on the right track.

A note about project choices: The handout, Putting It All Togetherincludes ideas for a final project to be included in the portfolio; you maywant to add some of your own ideas as well.

DAY 5: Classroom Ac t i v i t y

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W R A P - U P DAY

If your final day is a Friday and students have been keeping up, you canhave your portfolios due on Monday. Be sure to give out the portfolio sheetat the beginning of the unit so that students are clear on expectations well inadvance.

This final due date is cause for celebration—celebrate your students'achievements by asking them to present their projects and create displays oftheir work. Invite other classes or members of the school community to thepresentations. Any kind of celebration will offer immeasurable validation ofstudent work!

On the day that portfolios are due, reserve time at the beginning of class fora discussion of the unit. Use the questions below to structure your discus-sion. Out of this discussion, the class can develop a chart, or a more formalvisual presentation, of their findings. Then use this chart as a centerpiecefor a display of student work.

What questions did you investigate, individually and in groups?What conclusions did you develop?What methods did you use to find your answers?How does your information fit into the bigger picture? How does it contribute to your understanding of Biodiversity? Why areidentification and classification of arthrpods important to the study ofBiodiversity? What new questions do you have? How might you research the answers?

Have students assess each other's portfolios. Ask them to use the sameassessment sheet or provide other criteria for their assessment.

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F I NAL AS S E S S M E NT: Celebration o f Student Wo r k

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Barrett Klein was five years old when he realizedthat he wanted to combine art and insects as hislife’s work. "The greatest inspirational moment inmy life came as an abstract flurry when I was fiveyears old: I saw a painted lady butterfly lying deadon the driveway. I had never been struck greatlyby insects in particular, but when I found this and I looked at the form, Ifelt great inexplicable potential in my hands. And I realized that I could keep, exam-ine, and draw it, and suddenly everything seemed possible."

Barrett comes from an artistic family. "My parents are artists and own an art gallery.All of us, including my twin brother Arno and my sister Korinthia, would draw andpaint all the time. But there was more: From that point on I was drawn, not only to theaesthetics of the creature, but also to the idea that I could better understand its placein the world. If you’re inspired by the beauty of something, then I think you’re moreinclined to search for reasons why it exists and reasons to better understand it," hesaid.

By the time Barrett got to college, he was committed to both art and entomology. "Ireally wanted to do everything: to study fine arts, sculpture, filmmaking, biology, andeven some physics if I could squeeze it in." He majored in entomology but took asmany art courses as he could. In addition to his work as a display maker at theAmerican Museum of Natural History, Barrett is a working entomologist and filmmak-er.

"When I saw that butterfly in the driveway, I knew that my life would always involveinsects and art. Everything I do ends up being insect-related: All my films are oninsect subjects." He told us about a film he made in Panama that explored the struc-ture and behavior of plants and plant mimics. "I filmed leaf-cutter ants carting awaypieces of leaves and then spliced those images with ones of army ants carting awaypieces of katydids, which are mimics of leaves. It was a lot of fun," he said with alaugh.

Barrett says he chose to combine science and art because "I think that’s the mosteffective way of inspiring people to appreciate everything around us. If you can appre-ciate the form of a blade of grass not only for the beautiful streak of green and the tex-ture but also for its ability to produce oxygen or its function as food to countlessorganisms, from spittlebugs to leaf hoppers, and if you can communicate that to oth-ers, then you can motivate others to value everything on the planet," Barrett said.

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Sally Goodman was an art major at Hunter Collegein New York City when she visited the AmericanMuseum of Natural History as part of a class ingraphic arts.

"We came to see the exhibit on endangeredspecies, and afterward, I was just roaming around the Museum.I ended up in the Native American section, and it was there that I came across somevery beautifully drawn small pictures of fish. I was overwhelmed. They were the bestthing I had seen in the whole Museum," she recalled.

"It started me thinking: Wouldn’t it be wonderful if I could do that kind of stuff when Igraduated? I knew I’d need a job when I was finished with school, and I was con-cerned about whether I’d be able to find work that would be interesting and still payenough for me to live on. When I saw that drawing, a light went on in my head. Ithought: Somebody’s got to be doing that; maybe it could be me.

"I had been visiting the Museum since I was a child, but it had never before occurredto me that there were any illustrators working there. I thought only scientists workedthere. But here were illustrations—not photographs—and I suddenly saw the possibili-ties, a way that I could contribute something even though I did not have a sciencebackground."

Sally decided to find out more about what the Museum had to offer. "I spoke to thehead of the volunteer office, and she spoke to Dr. David Grimaldi, Chairman of theEntomology Department, who was looking for someone with pen-and-ink experienceto do some scientific illustrations."

She started out as a volunteer but soon had a paying job working for various scientists inthe department. Her official title is curatorial assistant. The work she does ranges frompinning and labeling specimens to making precise drawings using a microscope and aningenious device called a camera lucida. "It’s basically a mirror attached to the micro-scope that projects the image I’m seeing onto a sheet of paper. That allows me to trace theoutline of the specimen just as it appears under the microscope," Sally ex p l a i n e d .

She has done preparator work for a scientist who specializes in wasps. "He collectsnot only the wasps but also their nests. The nests are really beautiful, and in manyways the work I’m doing with them reminds me of installation art," she observed.

"I see lots of relationships between art and science. When I deal with insects—mount-ing, doing preparator work—it reminds me of things I do when I make art—composi-tion, organization, the kind of details I have to pay attention to. There really are manysimilarities," she said.

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Eric Quinter is Senior Scientific Assistant in theEntomology (arthropod studies) Department atthe American Museum of Natural History. Hehas been investigating arthropods since he wasa kid. Right now, he is studying various speciesof moths that live on (and eat) bamboo in NorthAmerica. Actually, it is the caterpillars that eat the bamboo.

We asked him how he decided to become an entomologist.

"I grew up in a rural area of Pennsylvania, and there weren’t many other kidsaround to play with. I didn’t have an awful lot to do except go out in the woodsand play with bugs and plants. So I got interested in all of nature simultaneously.I was interested in astronomy and birds and wildflowers and just about every-thing at the same time. My mother was a geologist, and she encouraged me andpointed me in the right direction. When I was seven, she bought me a little but-terfly-collecting kit for my birthday. It had a little dinky net in it, some pins, anda tiny little booklet, and that’s what got me going.

"I studied chemistry through college, and I thought I was going to be a chemistprofessionally, but it wasn’t very long before my adolescent interest in insectswon out. I have never regretted it because it’s an area where someone—anyone—who is patient and observant can make original contributions."

That is one of the things Eric loves about entomology. "In order to come up witha new discovery in physics or chemistry, for example, you have to know every-thing that all the other scientists already know just to start. With entomology, allyou have to do is go out there and look, and with enough perseverance you’llfind something."

Using himself as an example, Eric told us that so far he has found 15 species ofbamboo borer moths within a single family. "Ten of those had never been seenbefore I discovered them, and the other five are among the rarest things on thecontinent." Eric said this with pride, but then he added, "Now we find out they’renot rare at all. You just look for them and know how to find them, and there theyare."

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Eric told us that it is not only experts who make important discoveries in ento-mology. Students and hobbyists often find new species as well. The main thingyou need is to be a good observer. And, he admitted, you also need a lot ofpatience.

"You don’t need to be an Einstein to come up with brand-new information inentomology. A kid can make a new observation with insects just by finding cater-pillars, for example, on plants and raising them to see what they are.

"That’s what I had to do. There were no books—there still are no books—thatillustrate the majority of caterpillars of North American butterflies and moths. Soyou find this neat caterpillar and ask, ‘What is it?’ The only one way to find out isto raise it and see what it turns into. It’s a fascinating process. And if you do thatenough times, sooner or later you’re going to get something that no one knewbefore. It may be a familiar insect, but no one ever knew what its caterpillarlooked like."’

For Eric, the thrill of discovery has never waned. "I’ve collected as long as thirtyyears in one particular place in Pennsylvania, from the time I was a kid. In thelast year I collected there I was getting things I’d never seen in the previous 29years. You can never exhaust the cornucopia of insects," he said with a broadsmile.

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If he had not been seduced by his childhoodlove of collecting living things, Kefyn Catleymight still be a professional musician.

As a boy growing up in Wales, Kefyn remem-bers being "one of those kids who were alwayspoking under stones and looking into walls. I was fascinated by what I foundthere. I collected beetles, moths, birds’ nests, birds’ eggs. I had hundreds of birds’eggs, but the bugs were always more important to me.

"I was really, really young—under five—when I got one of those little magnifyingthings that you can put a bug in and look at it. Then, when I was six or seven,my older sister bought me a microscope, and that was it. I was hooked."

Except, Kefyn told us, he took a rather long detour, and it was nearly thirty yearsbefore he came back to his first love.

"I didn’t have much of a choice when I was school age. I really wasn’t all thatgood academically at the things that mattered, so I went into music." He studiedflute and other woodwind instruments, then got a job playing in a symphonyorchestra and teaching.

"After I’d been working as a professional musician for about twenty years, I gotto know some people in the neighborhood where I lived who were bug maniacs,just like I had been when I was younger. We started going out every weekendcollecting all sorts of bugs, spiders, and stuff, and I found myself spending moretime doing that than my music.

"It came to the point that I had to make a decision: Was I going to stay withmusic as a profession, or was I going to go into science proper, which is what Ialways wanted to do when I was younger?"

Kefyn chose science.

"I was in my thirties, and it took me ten years to change careers. I had an artsdegree and I needed a science degree. That led to a master’s, which led to aPh.D."

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Now he is a National Science Foundation Research Fellow working in theEntomology Department at the American Museum of Natural History. His spe-cialty is the identification and classification of Australian ground spiders.

Is he glad he made the change? Kefyn answers with an enthusiastic "Yes!"

He never got over his childhood fascination with arthropods, and he is happy tohave the chance to study them every day. But it is not a matter of studying"what’s out there," he argues.

"Where’s out there? It’s really here," he insists. "It’s not some place you go tolook at nature. We’re all in this together, all completely interdependent. I thinkit’s important to understand our own position in the world, to get the big pic-ture. And that’s something bugs help us do really quickly.”

Where does the name, arthropod, come from?The name comes from Greek words. In Greek, arthron, means "joint" and podmeans foot.

What are the common physical qualities of arthropods?Arthropods have jointed appendages, segmented bodies and a hard exoskeleton.

How many arthropods are there on Earth?There are approximately 1 million know species of arthropods. But that is onlya very small portion of the total number of arthropods out there. Within thesubphyla of insects alone, scientists suggest that there may be anywherebetween 8 million and 30 million scientifically unknown species of insects!

What are some common arthropods?Spiders, shrimp, crabs, butterflies, and ladybugs.

Arthropods are the most abundant, the most widely distributed, the most diverseand the most successful animals on Earth. Arthropods live on land in both tropicand polar regions, and every in between. They also live in salt, fresh and brackishwater all over the globe. In other words, there are millions and millions of arthro-pods, and they can be found in every nook, cranny and corner of the globe!

About three quarters of all known animals on Earth are arthropods, and about875,000 species of arthropods have been identified; but there are many species stillyet to be discovered, in areas as close as your back yard and as far off as the mostdistant tropical jungles and the deepest oceans. The estimated number of allundescribed species ranges from 10 to 100 million, and scientists believe thatmost of these undescribed species are arthropods. In the American Museum ofNatural History's arthropod collections alone, there are 100,000 species of arthro-pods still awaiting discovery.

All arthropods have jointed appendages, a segmented body and a hard exoskele-ton. The exoskeleton is a tough protective outer layer; because this layer is hard,arthropods must shed or molt it in order to grow. An arthropods body is dividedinto segments; some of the segments bear sets of jointed appendages, the equiva-lent of arms and legs on humans. Arthropods use their appendages for a varietyof functions, including locomotion (movement), eating, mating and even repro-

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duction and respiration. When they do move, arthropods can fly, crawl, hop,swim, burrow and walk. When they eat, most arthropods eat plants; but somearthropods eat blood, meat, carrion (dead creatures), dung or bacteria. In fact,many arthropods help to break down the waste of living creatures and the car-casses of dead ones, thereby performing a valuable function within their ecosys-tems.

It's not always easy! Many arthropods are very small, and you'll need a micro-scope to even see them. Many arthropods also look very different at differentstages of their life cycles. In fact, the egg, larva, pupa and adult stages don't lookanything alike; they may appear to be different animals when they are actuallythe same animal at different stages of development. And since they have differentneeds at different stages of development, they might be found in one habitat dur-ing one stage and a totally different one during the next stage.

The good news is that there are many species left to be discovered, and so youmight be the next person to discover one! Get started by observing arthropods inyour own backyard or in the cracks of the sidewalk near where you live. Insectsare the most common type of arthropod; in fact, there are more species of insectsthan there are species of all other kinds of animals combined. Insects have thejointed appendages, segmented bodies and hard exoskeletons of all arthropods;but their bodies have three distinct segments (head, thorax and abdomen), threepairs of legs, one pair of antennae and one pair of mandibles (kind of like teeth).

A list of all the known arthropos would go on for many pages. The chart on thenext page is only a partial listing of some of the more familiar ones to help youappreciate how very diverse they are.

The phylum Arthropoda is divided into four subphyla: Trilobita, Chelicerata,Crustacea, and Atelocerata. Take a look at some examples of animals from eachsubphylum.

Because there are more species of insects than there are species of all other kindsof animals combined, they warrant further descroption here. Insects have all thecharacteristics that define arthropods and additional features that define them asinsects. These additional features are: a body arranged into three distinct regions(head, thorax, and abdomen), three pairs of legs, one pair of antennae, and onepair of mandibles. Included is only a partial list of the orders in the classHexapoda.

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