PillBugsintheGarden!
1stGradeScienceUnit(HermitCrabs&NativeAnimals)
Objective:Studentswillbehaveasscientists,workinginpairstousetheir5senses
toinvestigatePillBugs(RolyPolys),atypeofIsopodorcloserelativeofHermit
Crabs.Botharepartofthegroupofanimalswecallcrustaceans(includeslobsters,
crabs,shrimp,crayfish,barnacles)
Materials:
Booksaboutpillbugs(readinadvanceoflessontoprimebackgroundknowledge)
suchas:I’maPillBugbyYukihisaTokudaandRoly-PolyPillBugsbyMollySmith
easel/chalkboardingardenforjottingdowngroupnotes/diagramofbodyparts
Somesamplepillbugs(foundunderrocks/incompostpilesetc.)
Chalk–enoughforeachchildtohaveapiece
Jarofsesameseeds(toshowsizeofbabypillbugs!)
Rulers/MagnifyingGlasses(optional)
Sit-uponsforeachkid
Measuringtapetoshowlengthof20ingiantpillbugrelative:deepseaisopod!
45minclass
5-10minGardenWalk:walkstudentsthelengthofgardenblacktoptoshedend–
aswalkaskthemtopointoutwhathaschangedsincelastvisit.Stoptolookatthese
changes/specificplantsandanswertheirquestions…
10min(groupseatedaroundeaselincourtyard)
LessonIntro:Lasttimewelookedatearthwormsinthegarden–hardworking
animaldecomposers!Todaywe’regoingtolookatanotherdecomposer(or
scavenger)importanttoourplanetthatalsokeepsoursoilhealthy:pillbugs!Why
doyouthinkwecallthembugswhentheyarenotinsects?
PillbugshaveLOTSofdifferentnames!RolyPoly,doodlebug,armadillobug,cheese
log,potatobug,chiggypig,etc.Whydotheyhavethosenames?Whydotheyroll
intoaball?Somepillbugscalledsowbugsorwoodlicedonotrollintoaball.
Pillbugsarerelatedtoyourclasspets:hermitcrabs!Howarepillbugslikehermit
crabs?Howaretheydifferent?Discusshabitat,food,appearance,behaviorofeach.
Writedownonchart/chalkboardaskidsgenerateideas.Usesit-uponsinshady
spaceifgrass/groundisdamp.
PillBugs
HermitCrabs
Habitat:
Food:
Appearance:
Behavior:
Predators:
15minPairwork
Thereare4,000differentkindsofpillbugs!Andyou’regoingtolookforsomeinthe
gardentoday!Basedonwhatyounowknow….whereshouldyoulookforthem?
(underrocks,insoil/compost/leafpiles)Rememberyouarescientistsusingyour5
senses….Withyourpartnergoandlookforsomepillbugs.Whenyoufindthemlet
themcrawlonyourhandandobservethemclosely.
Lookforthesethings:
Howmanylegsdotheyhave?
Howmanybodysegments?
Antennae?
Eyes?
Eggs/babies?(motherpillbugscarrythemunderneathontheirbellies!)
Doesitrollupornot?(rolypolyvs.sowbug)
Howaretheydifferentfromthewormswelookedat?
Asstudentsworkinpairstofindpillbugshandoutchalktoeachchild.Adults
checkin/assistasneeded.Oncestudentshavefound/observedanimalstheyshould
drawadiagramonsidewalktoshowthedifferentparts–countthoselegsand
segments!Howmanylegspersegment?!
5-10minLessonwrap-up
Studentsreturnpillbugstowheretheyfoundthem/rocksreplacedetc.Gatheragain
aroundeasel:lookatdiagram–didyourdrawingmatchthisone?Gooverparts
oncemore.Describehowtrueinsectshave6legs,spidershave8legs,pillbugshave
14legs(or7pairs!).Now…whatdoweeatthatpillbugsalsoliketoeat??Theyeat
ourscraps,right?Servestudents‘pillbugsnack’ofavailableveggie/herbfrom
garden(cilantro,chives,radish,spinachetc.)tossremnantsintocompost.*Ifteacher
allowssendsomepillbugsbacktoclasstoliveincagewithhermitcrabs(theywill
‘clean’cageasscavengerseatingleftoverhermitcrabfood!)
_________________________________________________________________________________________________
Resources:
http://thehappyhermitcrab.blogspot.com/2011/05/cleaning-with-bugs.html
https://en.wikipedia.org/wiki/Woodlouse
http://hermitcrabassociation.com/phpBB/viewtopic.php?p=852639
PillbugalsoRoly-Polyalsodoodlebug,armadillo bug, cheese log,potato bug, chiggy pig 4,000differentkindsofpillbugs!
Areinvertebrateanimals(nobackboneinsidethem!)likeworms–butunlike
wormshavehardexoskeleton:3mainbodyparts:head/middle/abdomen
antennaeonheadforfeeling/smellingtohelpitfindfood
Areinvertebrateanimals(backboneinsidethem!)likeworms–butunlikeworms
havehardexoskeleton
insectshave3pairsoflegs–pillbugshave7pairs,attachedto7segmentsinmiddle
ofbodysoNOTinsects!Havemorethan6legs–insectshave6legs–relatedto
crabs,shrimp,lobster!Hermitcrabs!Butliveonlandnotinwater-Canevenswima
bitiffallintowater(Giantdeep-seaIsopodlargestrelative–canbe20incheslong!)
likecrabshavegillstobreathebutuseonlandnotunderwater–butbecausehave
gillsmuststaywet/moistsorottinglogs,leafpiles,dampspotswheretheylive
Woodlouse(orsowbug)similarbutcan’trollup
Scavengers!Eatdeadplants,deadbugs,leftoverfoodscarpsfromhumans
Petfood,newspaper,cardboard
Eatstones/concretesobodieswork–whytheylivenearpeople
(concrete/sidewalks,walls,buildings)
Squarepoop!
RollintoballtoprotectselvesfrompredatorslikeantsBUTfrogs,spiders,lizards,
birds,shrewswillswallowwhole
Shedshellsasgrowbigger,rearhalffirst,thenfronthalf,theneattheshellfor
nutrition
Femalescarryeggsinwaterypouchontheirtummies,canbe200eggsinpouch!
whenhatchtheystayinpouchforanotherfewweeksthenleave.Theyarewhiteand
tiny(sesameseed!)butlookjustliketheirparents,asitgrowsitshedormoltsits
oldexoskeletonandgetsdarkerwitheachmolt!Startoutwith6legsthengrows7th
pairafterfirstmolt!
Infallsleepdeepingrounduntilspring(hibernate)orburrowintowarmlogs,even
inbuildings.Liveabout2years,somecanliveaslongas5years!
HermitCrabinfo:http://pethermitcrabs.org/anatomy/
Alsocrustaceans
Needwarmth/heat
Needcalcium(justlikepillbugs!)
Sweettooth,likefruits–inwildeatdecayingwood,grasses,plants
Nocturnal/liketoclimb
Gillstobreathebutnoexoskeletonoftheirown–sohavetofind/stealshells!
Moltbysheddingouterskin(buryselvesinsandtomolt)
Needhumidity/moisture
Freshwaterandsaltwaterneeded
Smellthroughtheirantennae
Socialanimalsthatliveingroups
live5-15years
10legsincludingfrontchelipeds(pincers)so5pairs
Due to their small size, hermit crabs have numerous natural predators all around
the world, which includes sharks, fish, cuttlefish, squid and octopuses.