The Little Known World of Flies - Biology Education
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1 MAGAZINE SUBHEAD THE LITTLE-KNOWN WORLD OF FLIES! Geetha Iyer To know the fly is to share a bit in the sublimity of Knowledge. -Prof Vincent G Dethier What makes flies different from a dragonfly or a butterfly? How do the lovely iridescent bluebottle and greenbottle flies help solve murders? What do insect bites, galls and chocolate have in common? Do flies have taste-buds? How do we introduce flies in science classrooms? This article explores the fascinating world of true flies, their incredible variety, and the diversity of services they provide us with, ending with an activity that teachers can use to unravel a little thought of aspect of fly life to students. Introduction Flies generally conjure a vision of dirt, disease and disgust. Our introduction to this image of flies is in school. A student is introduced to the humble housefly in a conclusive manner, leaving one with the impression that all flies are repulsive creatures. Limited scientific information about houseflies is accompanied by a vivid description of the mouth parts being used to drink from muck, thereby leaving an indelible image of a fly only as a vermin. A students’ next encounter with the fly is during a lesson on health, as the carrier of diseases, thereby nailing the coffin on the possibility of flies being anything but loathsome creatures. No doubt there are many flies that bite and spread disease. But, do all flies deserve such an image? It’s time someone spoke up for flies, whose colour, variety and elegance should not be judged only by the housefly, or the behaviour restricted to a frolic in decomposing heaps, although this frolic is not SECTION HEADER Brown Muscid Fly
Transcript of The Little Known World of Flies - Biology Education
18I WONDER... MAGAZINE SUBHEAD
THE LITTLE-KNOWNWORLD OF FLIES!
Geetha Iyer
ToknowtheflyistoshareabitinthesublimityofKnowledge.-ProfVincentGDethier
Whatmakesfliesdifferentfromadragonflyorabutterfly?Howdothelovelyiridescentbluebottleandgreenbottleflieshelpsolvemurders?Whatdoinsectbites,gallsandchocolatehaveincommon?Doflieshavetaste-buds?Howdoweintroducefliesinscienceclassrooms?Thisarticleexploresthefascinatingworldoftrueflies,theirincrediblevariety,andthediversityofservicestheyprovideuswith,endingwithanactivitythatteacherscanusetounravelalittlethoughtofaspectofflylifetostudents.
Introduction
Fliesgenerallyconjureavisionofdirt,diseaseanddisgust.
Ourintroductiontothisimageoffliesisinschool.Astudentisintroducedtothehumblehouseflyinaconclusivemanner,leavingonewiththeimpressionthatallfliesarerepulsivecreatures.Limitedscientificinformationabouthousefliesisaccompaniedbyavividdescriptionofthemouthpartsbeingusedtodrinkfrommuck,therebyleavinganindelibleimageofaflyonlyasavermin.Astudents’nextencounterwiththeflyisduringalessononhealth,asthecarrierofdiseases,therebynailingthecoffinonthepossibilityoffliesbeinganythingbutloathsomecreatures.
Nodoubttherearemanyfliesthatbiteandspreaddisease.But,doallfliesdeservesuchanimage?It’stimesomeonespokeupforflies,whosecolour,varietyandeleganceshouldnotbejudgedonlybythehousefly,orthebehaviourrestrictedtoafrolicindecomposingheaps,althoughthisfrolicisnot
SECTION HEADER
Brown Muscid Fly
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withoutbenefit,andIshallsoontellyouhowandwhy.
Althoughtherearemanyinterestingaspectsoffliesthatonecandwellon,inthisarticle.Iwillconfinemyselftointroducingyoutoasmallgrouponecanchanceupon,eveninurbanenvironments;andtothediversityandservicessomefliesinthisorderperform.Ishallconcludewithhowthemouthpartsofahouseflycanbeobservedinamannerthatismoreinterestingthanlookingataslide,withartificialcolours,underamicroscope.
Arefliesfilthy?
Fliesareamongthecleanestofinsects,andareveryparticularabouttheirownhygiene.Infact,humanscouldtakealessonortwoonpersonalhygienefromthem.Observeaflycloselynexttime,andyouwillnoticehowfrequentlyitcleansitself.
Ifaflydoesvisitdecomposingmaterialsforitsnutrientrequirements,itdoessotosatisfyitsnutritionalneeds.Afterall,wehumans,too,likefoodgrowingondecomposingmatter,don’twe?Ifyouweretotakeasurveyofyourdailyintakeoffood,you’dbesurprisedbyhowmanyofourfavouritefoodscomefromdecomposingmatter!Takemushrooms,forexample,thatgrowsoverywelloncowdung;orKombucha,ahealthdrink,madebyallowingcertainyeastandbacterialspecies(kombuchacultureappearinglikeaslimypancake)togrowinasugarysolutionofblackorgreentea!Whatavarietyoffermentingfooditemsweconsume!
Perhaps,someoftheblameforthediseasesthatfliestransmitliesinhumanstoo!Ifwegavemorethoughttoourhygieneandsanitation,flieswouldn’tfrequentourenvironmentsofreely,wouldthey?
Whatisafly?
InaworldpopulatedbytheButterfly,Dragonfly,Scorpionfly,Mayfly,Stonefly,Firefly,Owlfly,andsoon,whatisthisinsectthatissimplycalledafly?
Theinsectslistedabovearenotfliesfromanentomologists’pointofview.TruefliesareinsectsthatbelongtotheorderDiptera,anamethatdescribestheirdefiningfeature–theseflieshaveonlyonepairofwings(inLatin,di:meanstwo,andptera:meanswings).Incontrast,insectsbelongingtoallotherinsectordershavetwopairsofwings!Whatmakesthisevenmoreinteresting
Twowingsseemtohavemadethemnolessagilethanotherinsects,eminentlydeservingthename“fly”!Considerthesefacts,notlearntinaclassonflies.Fliesareincrediblynimbleinflight.Thebestaerialistsamonginsects,theycanhover,flybackwards,turninplaceandflyupsidedowntolandontheceiling!Theyhavesensors-speedindicators-locatedinapartoftheirantennacalledarista,togaugetheirflightspeed.Ahousefly’swingspeedisabout190beatsinasinglesecond!Thefastestmuscularcontractionahumanbeingcanmanageclocksattentimespersecond.Nomysterythen,whyitissodifficulttoswatafly!
Howmanyfliesarethereintheworld?
Nooneknowsanexactnumber.Asmentionedbefore,truefliesbelongtotheorderDiptera,whichisthethirdlargestgroupamonginsects.Mosquitoesbelongtothisordertoo!Morethan1,60,000speciesofflieshavealreadybeendescribedbyspecialists;withverymanymoreyettobeclassified,andseveralmoretobediscovered.Asyoucantell,thismeansaverylargenumber,indeed!
FlyServicesandDiversity
Everyfamilyofanimals(includinghumans)onthisplanet,havetheirshareofvillainsandheroes;and,flyfamiliesarenoexception!Therearemany
isthattrueflieshaveevolvedfromfour-wingedancestorsinthePermian250MYA(millionyearsago).Intheirmodern-daydescendants,however,thissecondpair-thehindwings-hasbecomereducedtoclub-shapedstructures,calledHalteres.Eachhalterecanbelikenedtoagyroscope;theyareessentialinmaintainingbalanceduringflight.
interestingthingsonecanlearnbyexploringtheworldofflies.Ishalldescribeahandfulofthesehere.
A.FliesasPollinators:Itisawell-establishedfactthatplantsandinsectshavemutuallyinfluencedtheevolutionoftheirdiversity.Fliesarebelievedtobeforemostamongstthepollinatorsofearlyfloweringplants;yettheirroleinsuchanimportantserviceremainsrelativelyunknown.Ofthe150dipteranfamilies,flyspeciesofnearly70families(Evenhuisetal.2008)areknowntovisitflowerstofeed.Ithasbeendocumentedthatfliesaretheprimarypollinatorsforseveralhundredsofwildorcultivatedplants(closeto550,accordingtoLarsenetal.2001).Pollinationbyfliesis,generally,referredtoasmyophily.
Whatmakesfliessuchgoodpollinators?Theyarenotonlyabundant,butarealsopresentinwidelydiversehabitats.Theyarethemostimportantpollinatorsinalpineorarcticregions,wherepollinationbybeesisreduced.Intheunder-storeyregionsofforests,fliesarebelievedtobeimportantinpollinatingawidevarietyofshrubswithsmall,inconspicuousordioeciousflowers.Theirabundantpresenceiscomplimentedbyanatomicalfeatures,suchasvariationsinmouthparts,tonguelength,sizeanddegreeofpilosity(hairiness);allofwhichcontributetomakingfliessomeofthemosteffectivepollinators,ever.Plantswouldprobablynodtheir(flower)headsinagreement!
Fliesvisitflowersfortheirownreasons:nectarandpollenaresourcesoffood.Theproteinsinpollenarenecessaryforsomefliestoreproduce.Somefliesvisitflowerstolaytheireggs,ensuringthattheirdevelopinglarvaehaveeasyaccesstofood–theflowerheads,seedsordevelopingfruits.And,so,forsomeflies,flowersaremating(dating?)sites.Howconvenient!
Myfavouriteamongthesepollinators,withoutdoubt,wouldbethebeautifulandcolourfulfliesoftheFamilySyrphidae,commonlycalledhoverfliesorflowerflies.Atfirstglance,ahoverflywouldhardlystrikeoneasafly,lookingmorelikeabee,thanafly.Eachofthem,however,hassuchalongproboscis,thatitcangointothedeepestofcorollastosipnectar.Thismakesthemexcellentpollinators,servingawiderangeofplants,andsecondonlytobeesinthisrole.Alargenumberoffoodsweconsumearepollinatedbyhoverflies.Lookforthesefliesamongsttheflowersofmango,apple,pear,cherry,andstrawberry;oramong
Chrysops sp. Biting fly.
coriander,onion,carrot,pepper,andcapsicum,tonameafew.
Thelifeofaninsectisfulloftricksandtreatsthatcontributetoitssurvival.Onesuchfeatureisthedifferingfoodsourceforlarvaeandadults.Adultinsectsdon’tcompetewiththeiryoungonesforfood.Thus,whiletheadulthoverflyisavegetarianhelpingwithpollination;it’slarvaeormaggotsareinsectivorous,feedingonawiderangeofprey-mostlyaphidsandothersapsuckinginsects,andtherebyactingaspestcontrolagents-anotherfactaboutfliesthatrarelyreceivesanyattention.Thus,syrphidfliesareimportantaspollinatorsandpestcontrollers.
Hover fly Mesembrius quadrivittatus.
Blow fly-Blue bottle fly, Calliphora sp.
Plantsputoutavarietyofodourstoattractinsects.Theputridsmellofdecayingfleshfromsomeflowersattractscarrionanddungflies,belongingtotheFamilyCalliphoridae.Theyvisittheseflowers,expectingtofinddecayingfleshand,pollinatethem,evenastheyleavedisappointed.Commonlycalledblowflies,thebluebottleandgreenbottlefliesarequitecolourfulandattractive.Interestingly,theyplayanimportantroleinforensics(seebelow).
Blow fly-Blue bottle fly, Calliphora sp.
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withoutbenefit,andIshallsoontellyouhowandwhy.
Althoughtherearemanyinterestingaspectsoffliesthatonecandwellon,inthisarticle.Iwillconfinemyselftointroducingyoutoasmallgrouponecanchanceupon,eveninurbanenvironments;andtothediversityandservicessomefliesinthisorderperform.Ishallconcludewithhowthemouthpartsofahouseflycanbeobservedinamannerthatismoreinterestingthanlookingataslide,withartificialcolours,underamicroscope.
Arefliesfilthy?
Fliesareamongthecleanestofinsects,andareveryparticularabouttheirownhygiene.Infact,humanscouldtakealessonortwoonpersonalhygienefromthem.Observeaflycloselynexttime,andyouwillnoticehowfrequentlyitcleansitself.
Ifaflydoesvisitdecomposingmaterialsforitsnutrientrequirements,itdoessotosatisfyitsnutritionalneeds.Afterall,wehumans,too,likefoodgrowingondecomposingmatter,don’twe?Ifyouweretotakeasurveyofyourdailyintakeoffood,you’dbesurprisedbyhowmanyofourfavouritefoodscomefromdecomposingmatter!Takemushrooms,forexample,thatgrowsoverywelloncowdung;orKombucha,ahealthdrink,madebyallowingcertainyeastandbacterialspecies(kombuchacultureappearinglikeaslimypancake)togrowinasugarysolutionofblackorgreentea!Whatavarietyoffermentingfooditemsweconsume!
Perhaps,someoftheblameforthediseasesthatfliestransmitliesinhumanstoo!Ifwegavemorethoughttoourhygieneandsanitation,flieswouldn’tfrequentourenvironmentsofreely,wouldthey?
Whatisafly?
InaworldpopulatedbytheButterfly,Dragonfly,Scorpionfly,Mayfly,Stonefly,Firefly,Owlfly,andsoon,whatisthisinsectthatissimplycalledafly?
Theinsectslistedabovearenotfliesfromanentomologists’pointofview.TruefliesareinsectsthatbelongtotheorderDiptera,anamethatdescribestheirdefiningfeature–theseflieshaveonlyonepairofwings(inLatin,di:meanstwo,andptera:meanswings).Incontrast,insectsbelongingtoallotherinsectordershavetwopairsofwings!Whatmakesthisevenmoreinteresting
Twowingsseemtohavemadethemnolessagilethanotherinsects,eminentlydeservingthename“fly”!Considerthesefacts,notlearntinaclassonflies.Fliesareincrediblynimbleinflight.Thebestaerialistsamonginsects,theycanhover,flybackwards,turninplaceandflyupsidedowntolandontheceiling!Theyhavesensors-speedindicators-locatedinapartoftheirantennacalledarista,togaugetheirflightspeed.Ahousefly’swingspeedisabout190beatsinasinglesecond!Thefastestmuscularcontractionahumanbeingcanmanageclocksattentimespersecond.Nomysterythen,whyitissodifficulttoswatafly!
Howmanyfliesarethereintheworld?
Nooneknowsanexactnumber.Asmentionedbefore,truefliesbelongtotheorderDiptera,whichisthethirdlargestgroupamonginsects.Mosquitoesbelongtothisordertoo!Morethan1,60,000speciesofflieshavealreadybeendescribedbyspecialists;withverymanymoreyettobeclassified,andseveralmoretobediscovered.Asyoucantell,thismeansaverylargenumber,indeed!
FlyServicesandDiversity
Everyfamilyofanimals(includinghumans)onthisplanet,havetheirshareofvillainsandheroes;and,flyfamiliesarenoexception!Therearemany
isthattrueflieshaveevolvedfromfour-wingedancestorsinthePermian250MYA(millionyearsago).Intheirmodern-daydescendants,however,thissecondpair-thehindwings-hasbecomereducedtoclub-shapedstructures,calledHalteres.Eachhalterecanbelikenedtoagyroscope;theyareessentialinmaintainingbalanceduringflight.
interestingthingsonecanlearnbyexploringtheworldofflies.Ishalldescribeahandfulofthesehere.
A.FliesasPollinators:Itisawell-establishedfactthatplantsandinsectshavemutuallyinfluencedtheevolutionoftheirdiversity.Fliesarebelievedtobeforemostamongstthepollinatorsofearlyfloweringplants;yettheirroleinsuchanimportantserviceremainsrelativelyunknown.Ofthe150dipteranfamilies,flyspeciesofnearly70families(Evenhuisetal.2008)areknowntovisitflowerstofeed.Ithasbeendocumentedthatfliesaretheprimarypollinatorsforseveralhundredsofwildorcultivatedplants(closeto550,accordingtoLarsenetal.2001).Pollinationbyfliesis,generally,referredtoasmyophily.
Whatmakesfliessuchgoodpollinators?Theyarenotonlyabundant,butarealsopresentinwidelydiversehabitats.Theyarethemostimportantpollinatorsinalpineorarcticregions,wherepollinationbybeesisreduced.Intheunder-storeyregionsofforests,fliesarebelievedtobeimportantinpollinatingawidevarietyofshrubswithsmall,inconspicuousordioeciousflowers.Theirabundantpresenceiscomplimentedbyanatomicalfeatures,suchasvariationsinmouthparts,tonguelength,sizeanddegreeofpilosity(hairiness);allofwhichcontributetomakingfliessomeofthemosteffectivepollinators,ever.Plantswouldprobablynodtheir(flower)headsinagreement!
Fliesvisitflowersfortheirownreasons:nectarandpollenaresourcesoffood.Theproteinsinpollenarenecessaryforsomefliestoreproduce.Somefliesvisitflowerstolaytheireggs,ensuringthattheirdevelopinglarvaehaveeasyaccesstofood–theflowerheads,seedsordevelopingfruits.And,so,forsomeflies,flowersaremating(dating?)sites.Howconvenient!
Myfavouriteamongthesepollinators,withoutdoubt,wouldbethebeautifulandcolourfulfliesoftheFamilySyrphidae,commonlycalledhoverfliesorflowerflies.Atfirstglance,ahoverflywouldhardlystrikeoneasafly,lookingmorelikeabee,thanafly.Eachofthem,however,hassuchalongproboscis,thatitcangointothedeepestofcorollastosipnectar.Thismakesthemexcellentpollinators,servingawiderangeofplants,andsecondonlytobeesinthisrole.Alargenumberoffoodsweconsumearepollinatedbyhoverflies.Lookforthesefliesamongsttheflowersofmango,apple,pear,cherry,andstrawberry;oramong
Chrysops sp. Biting fly.
coriander,onion,carrot,pepper,andcapsicum,tonameafew.
Thelifeofaninsectisfulloftricksandtreatsthatcontributetoitssurvival.Onesuchfeatureisthedifferingfoodsourceforlarvaeandadults.Adultinsectsdon’tcompetewiththeiryoungonesforfood.Thus,whiletheadulthoverflyisavegetarianhelpingwithpollination;it’slarvaeormaggotsareinsectivorous,feedingonawiderangeofprey-mostlyaphidsandothersapsuckinginsects,andtherebyactingaspestcontrolagents-anotherfactaboutfliesthatrarelyreceivesanyattention.Thus,syrphidfliesareimportantaspollinatorsandpestcontrollers.
Hover fly Mesembrius quadrivittatus.
Blow fly-Blue bottle fly, Calliphora sp.
Plantsputoutavarietyofodourstoattractinsects.Theputridsmellofdecayingfleshfromsomeflowersattractscarrionanddungflies,belongingtotheFamilyCalliphoridae.Theyvisittheseflowers,expectingtofinddecayingfleshand,pollinatethem,evenastheyleavedisappointed.Commonlycalledblowflies,thebluebottleandgreenbottlefliesarequitecolourfulandattractive.Interestingly,theyplayanimportantroleinforensics(seebelow).
Blow fly-Blue bottle fly, Calliphora sp.
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Robustly,builtfliesofthefamilyTabanidae,commonlycalledhorseflies,or,simply,tabanidflies,aremostlybloodthirstyflies;butsomeofthemarelesserfiends.Theyareconsideredpests,sincemanyspeciesbiteanimalsandhumans.But,some,withtheirspectacularlylongtonguespollinateflowersthathavelongtube-shapedcorollas(imageTabanidfly–Philolichesp.).InthefemalesofcertainPhilolichespecies,theverylongtongueisadaptedtoperformthedualfunctionsofbloodsuckingandnectarsipping!Rhino-myophilyisthetermthatdescribespollinationbylong-tonguedflies.
Thatuniversallylovedfood-chocolate,owesitsexistencetoflies!Midgesareflies.ThosebelongingtothefamiliesCeratopogonidaeandCecidomyiidae,areknownmorefortheirbitingandgall-forminghabitsthanforanythingapplaudable.But,notallofthemarebitersorgallers!Thecocoaplantreliesonsmallmidgespeciesofthesetwofamiliestopollinateitstinywhiteblossoms,producedonthelowerpartsofitsmaintrunk.Themushroomishodouroftheflowerattractsmidges,justaschocolatesattractus.Otherthanaparticularspeciesofhoverfliesinsomerestrictedregions,cocoaplantsneedmidgestoproducefruit.Nomidge,nococoa,nochocolates!DoIhearshoutsofthreecheersformidges?Doremembertothankflies,thenexttimeyoufeastonchocolatesorcocoa.
B.FliesinForensics:Fromthelivingtothedead,fromflowerstocorpses-asfliessearchfornutrition,theiractionsbestowindirectassistancetootherlivingorganisms.Flieshelphumansincriminalinvestigations,andareafavouritewithforensicentomologists.
Blowfliesarenotjustpollinators;theirlovefordecomposinganimalmatterdrawsthemtothedead.Infact,theyarethefirsttoarriveatadeath
Blowfly – Greenbottle, Lucilla sp.
Golden blowfly.
Tabanid fly - Philoliche spp. Photo by Sanjay Sondhi
Tabanid fly - Philoliche spp. Photo by Sanjay Sondhi
A midge
Otherspeciesofflies,suchastheblacksoldierfly,thecoffinfly,theblackscavengerfly,membersofHydroteasp.ofFamilyMuscidae,andhumpbackedflies,areequallyusefulinprovidingimportantinformationduringautopsies.Theirservicesrangefromdeterminingwhetherthecorpsehasbeenmovedfromtheoriginalsceneofcrime,informationabouttoxicology,and,inmanycases,eveninfixingthetimeofdeath.
“TheWashingAwayofWrongs"writtenin1247ADbySungTz’u,acrimeinvestigatorinChina,isthefirstrecordoffliesincriminalinvestigation.Thisbookisthefirsttolaythefoundationsofforensicentomology.AmurderhappensinaChinesevillage,andthedeadman’sbodyisdiscovered,cutupbadly.Unabletomakeanyheadwaywithhisinvestigation,theinvestigatorasksallthevillagerstobringtheirsickles,andlayitonthegroundinfrontofhim.Soonfliesswarmtoonesickle.Theownerhadnotwashedhissicklewell,andtheflieswereattractedtothe
scene!Soacuteisitssenseofsmell,thatablowflycanapparentlysmelladeadbody16kmaway!Membersofthisfamilyareknownbyvariousnames–bluebottles,greenbottles.Theyareeasilyrecognised-lookinglikealargerversionofthecommonhousefly.Whyaretheydrawntodeadbodies,onemayask?Blowflieslookatdeadbodiesasafoodsourcefortheiryoungones.Theylaytheireggsintheorificesofcorpses,andmaggotshatchoutin24hours.Fleshflies,oftheFamilySarcophagidae,givebirthtoliveyoungonesonthefleshofthecorpses!Howdoesthisbehaviourhelpus?Thelifehistoryofablowflyiswell-documented,providingamineofinformationduringpost-mortemsofthecorpsesthatattractthem.
Flesh Fly
odourofblood.Theownerconfessestothecrime,and,so,begantheuseoffliestosolvecrimes.
IfyouareafanoftheTVserial“Bones”,then,surely,youmustalreadybeawareofthenuancesofforensicentomology,fromtheworkofthecharacterJackHodgins,aforensicentomologist-cum-botanist.
Therearemanyothersuchinterestinginstancesofcrimes,solvedwiththehelpofflies.
C.FliesasPestControlAgents:Agriculturalresearchersandpragmaticfarmerswillvouchfortheservicesprovidedbyfliesinkeepingacheckonphytophagousinsects.Therearemanyfliesthathelpintheseroles,butdescribedbelowareafewfavouritesofmine.
Icallthemjewelflies,andnotlong-leggedflies,astheyaremorecommonlycalled.Theirmorecommonnamepointstotheirlonglegs,astrikingfeatureofthefliesofthefamilyDolichopodidae.Jewelfliesareslenderanddaintylittleflies,sportingbeautifulcolours.Mostlyblue,green,andgoldwithametallicshine,thereareafewoftheseecologicallyimportantfliesthatsportadullgreycolourtoo.Lookingverymuchlikeaflyonstilts;youcannotmissthem.Theyhaveaslenderbody,prominenteyes,andtheirtrademarklonglegs.Malesshowofftheirlonglegstoattractfemales;quitetheoppositeofthehumanspeciesitwouldseem!Lavishmanoeuvresandsignalsmarkthecourtshipbehaviourofmales.Manyofthesefliesmateinflight,whichisanexhaustingpractice;so,sometimesmalescreateanillusionbysportingapatterntoconthefemalesintothinkingthattheyarematinginflight.
Foundinmosthabitats,Jewelfliesarepredatory,feedingonawidevarietyofinvertebrates-aphids,thrips,spidermites,andcollembolans.Infact,aparticularspeciesofDolichopuspreysonmosquitolarvae!Somespeciesarescavengerstoo.Thesefliesarefidgety;soonehastobereallystillandsilenttowatchthem.
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Robustly,builtfliesofthefamilyTabanidae,commonlycalledhorseflies,or,simply,tabanidflies,aremostlybloodthirstyflies;butsomeofthemarelesserfiends.Theyareconsideredpests,sincemanyspeciesbiteanimalsandhumans.But,some,withtheirspectacularlylongtonguespollinateflowersthathavelongtube-shapedcorollas(imageTabanidfly–Philolichesp.).InthefemalesofcertainPhilolichespecies,theverylongtongueisadaptedtoperformthedualfunctionsofbloodsuckingandnectarsipping!Rhino-myophilyisthetermthatdescribespollinationbylong-tonguedflies.
Thatuniversallylovedfood-chocolate,owesitsexistencetoflies!Midgesareflies.ThosebelongingtothefamiliesCeratopogonidaeandCecidomyiidae,areknownmorefortheirbitingandgall-forminghabitsthanforanythingapplaudable.But,notallofthemarebitersorgallers!Thecocoaplantreliesonsmallmidgespeciesofthesetwofamiliestopollinateitstinywhiteblossoms,producedonthelowerpartsofitsmaintrunk.Themushroomishodouroftheflowerattractsmidges,justaschocolatesattractus.Otherthanaparticularspeciesofhoverfliesinsomerestrictedregions,cocoaplantsneedmidgestoproducefruit.Nomidge,nococoa,nochocolates!DoIhearshoutsofthreecheersformidges?Doremembertothankflies,thenexttimeyoufeastonchocolatesorcocoa.
B.FliesinForensics:Fromthelivingtothedead,fromflowerstocorpses-asfliessearchfornutrition,theiractionsbestowindirectassistancetootherlivingorganisms.Flieshelphumansincriminalinvestigations,andareafavouritewithforensicentomologists.
Blowfliesarenotjustpollinators;theirlovefordecomposinganimalmatterdrawsthemtothedead.Infact,theyarethefirsttoarriveatadeath
Blowfly – Greenbottle, Lucilla sp.
Golden blowfly.
Tabanid fly - Philoliche spp. Photo by Sanjay Sondhi
Tabanid fly - Philoliche spp. Photo by Sanjay Sondhi
A midge
Otherspeciesofflies,suchastheblacksoldierfly,thecoffinfly,theblackscavengerfly,membersofHydroteasp.ofFamilyMuscidae,andhumpbackedflies,areequallyusefulinprovidingimportantinformationduringautopsies.Theirservicesrangefromdeterminingwhetherthecorpsehasbeenmovedfromtheoriginalsceneofcrime,informationabouttoxicology,and,inmanycases,eveninfixingthetimeofdeath.
“TheWashingAwayofWrongs"writtenin1247ADbySungTz’u,acrimeinvestigatorinChina,isthefirstrecordoffliesincriminalinvestigation.Thisbookisthefirsttolaythefoundationsofforensicentomology.AmurderhappensinaChinesevillage,andthedeadman’sbodyisdiscovered,cutupbadly.Unabletomakeanyheadwaywithhisinvestigation,theinvestigatorasksallthevillagerstobringtheirsickles,andlayitonthegroundinfrontofhim.Soonfliesswarmtoonesickle.Theownerhadnotwashedhissicklewell,andtheflieswereattractedtothe
scene!Soacuteisitssenseofsmell,thatablowflycanapparentlysmelladeadbody16kmaway!Membersofthisfamilyareknownbyvariousnames–bluebottles,greenbottles.Theyareeasilyrecognised-lookinglikealargerversionofthecommonhousefly.Whyaretheydrawntodeadbodies,onemayask?Blowflieslookatdeadbodiesasafoodsourcefortheiryoungones.Theylaytheireggsintheorificesofcorpses,andmaggotshatchoutin24hours.Fleshflies,oftheFamilySarcophagidae,givebirthtoliveyoungonesonthefleshofthecorpses!Howdoesthisbehaviourhelpus?Thelifehistoryofablowflyiswell-documented,providingamineofinformationduringpost-mortemsofthecorpsesthatattractthem.
Flesh Fly
odourofblood.Theownerconfessestothecrime,and,so,begantheuseoffliestosolvecrimes.
IfyouareafanoftheTVserial“Bones”,then,surely,youmustalreadybeawareofthenuancesofforensicentomology,fromtheworkofthecharacterJackHodgins,aforensicentomologist-cum-botanist.
Therearemanyothersuchinterestinginstancesofcrimes,solvedwiththehelpofflies.
C.FliesasPestControlAgents:Agriculturalresearchersandpragmaticfarmerswillvouchfortheservicesprovidedbyfliesinkeepingacheckonphytophagousinsects.Therearemanyfliesthathelpintheseroles,butdescribedbelowareafewfavouritesofmine.
Icallthemjewelflies,andnotlong-leggedflies,astheyaremorecommonlycalled.Theirmorecommonnamepointstotheirlonglegs,astrikingfeatureofthefliesofthefamilyDolichopodidae.Jewelfliesareslenderanddaintylittleflies,sportingbeautifulcolours.Mostlyblue,green,andgoldwithametallicshine,thereareafewoftheseecologicallyimportantfliesthatsportadullgreycolourtoo.Lookingverymuchlikeaflyonstilts;youcannotmissthem.Theyhaveaslenderbody,prominenteyes,andtheirtrademarklonglegs.Malesshowofftheirlonglegstoattractfemales;quitetheoppositeofthehumanspeciesitwouldseem!Lavishmanoeuvresandsignalsmarkthecourtshipbehaviourofmales.Manyofthesefliesmateinflight,whichisanexhaustingpractice;so,sometimesmalescreateanillusionbysportingapatterntoconthefemalesintothinkingthattheyarematinginflight.
Foundinmosthabitats,Jewelfliesarepredatory,feedingonawidevarietyofinvertebrates-aphids,thrips,spidermites,andcollembolans.Infact,aparticularspeciesofDolichopuspreysonmosquitolarvae!Somespeciesarescavengerstoo.Thesefliesarefidgety;soonehastobereallystillandsilenttowatchthem.
76I WONDER... MAGAZINE SUBHEAD
SoldiersandRobbersperformingsimilarfunctionscouldhappenonlyintheworldofinsects!SoldierfliesbelongtothefamilyStratiomyidaewhereastherobberflies,toFamilyAsilidae.Intheworldofflies,therobbersattackandcatchpestsmoreoftenthanthesoldiers;thelatter’sservicesarevariedandincludesomepredation.
Robberfliesarethemostpredatorygroupintheworldofflies,andfeedexclusivelyoninsects.Theirnameistrulyrepresentativeoftheirbehaviour.Theyareaggressivehunters,ambushtheirprey,andarestronglybuiltwithpowerfulmusclesthathelpthemcaptureinsectsinflight!Theyarerobbersinappearancetoo,sportingatuftofstiffbristles-likeamoustache-betweentheireyes,thataremountedprominentlyontheirhead.Infact,theterm‘mystax’usedtodescribethesebristlesisderivedfromtheGreekwordmeaning‘moustache’or‘upperlip’.Thesecosmopolitanfliesenjoyaworldwidedistribution,butarecommonintropicalandsubtropicalareas,andabundantindryandsunnyaridorsemi-aridzones.
Robberfliescanveryeasilybeidentifiedbytheirlongslenderbodies,withthetipsoftheirabdomensvisiblebeyondthefoldedwings.Themystaxisunmistakable,andtheheadandthoraxishairy.Becauseoftheirlongtaperingabdomen,combinedwithbrightlycoloured–black,grey,redoryellow-patterns,theyareoftenmistakenforwasps.Someofthemwithstout,hairybodies,mimicbees;whileotherswithslender,lithebodies,imitatedamselflies.Asyoucansee,theserobbershavemasteredtheartofdisguisetoo!Theirperchisanotherwayofidentifyingthesefliesinahabitat.Robbersliketoperchonthetopmostendofaplantwaitingtoseizeprey.
Robbersinjectcapturedpreywithsalivacontainingneurotoxicandproteolyticenzymes,killingthem.Bothadultandjuvenilerobberfliespreyonawidevarietyofinsects,thusservingtheimportantecologicalfunctionofkeepingacheckontheinsectfaunainanyarea.
Soldierfliesarediverseintheirhabitsandfoodpreferences,butaremainlyrecognisedbytheiruniquewingvenation.Somesoldiersarepollinators;someassistwithforensics;othersarehelpfulincompostingwaste;whileafewofthemarepredatory.Thebrightlycolouredonesresemblewaspsandbees.Soldiersmaybesaprophagus,myophagousorpredatory;andaregenerallyfoundclosetoaquatichabitatsinwhichtheirlarvaedevelop.Thesefliesarenotawidelyresearchedgroup,exceptHermetiaillucens,whichiscommonlycalledtheblacksoldierfly.Weshalllookatthisflyagain,inthenextsection.
D.FliesinComposting:Theblacksoldierfly,Hermetiaillucens,isnowbeingextensivelyusedtocompostwastes.However,thisprocessisyettofindwiderapplicationinIndia,andiscurrentlybeingpractisedonlybyafewresearchersinPune.
Long-legged flies
Green Soldier Fly
Small Soldier Fly
Black Soldier Fly
Soldier Fly Crane Fly
Mating Robber Flies
Thecompostpitinmybackyardhasblacksoldierflies.Thephotogivenhereisofoneofthemhelpingdecomposewaste,alongwithotherorganisms.
E.FliesinScientificResearch:Fruitflieshavebeeninourlaboratoriesfordecadesnow,andcontinuetoplayawell-knownandextensivelydocumentedroleinoureffortstounderstandgeneactionandinheritancemechanisms.
Whatislesswell-knownistheroleoffliesinsomeotherkindsofexperiments.In2007,forexample,someresearchersatHarvardUniversitybuiltaroboticfly.Weighing60mg,andwithawingspanof3cm,thislife-likeflywasmodelledtoimitatethemovementsofarealfly.Madeofultra-thincarbonfibre,theroboticflyhasawingbeatof110beats/second.Thiseffortisthefirststepto
76I WONDER... MAGAZINE SUBHEAD
SoldiersandRobbersperformingsimilarfunctionscouldhappenonlyintheworldofinsects!SoldierfliesbelongtothefamilyStratiomyidaewhereastherobberflies,toFamilyAsilidae.Intheworldofflies,therobbersattackandcatchpestsmoreoftenthanthesoldiers;thelatter’sservicesarevariedandincludesomepredation.
Robberfliesarethemostpredatorygroupintheworldofflies,andfeedexclusivelyoninsects.Theirnameistrulyrepresentativeoftheirbehaviour.Theyareaggressivehunters,ambushtheirprey,andarestronglybuiltwithpowerfulmusclesthathelpthemcaptureinsectsinflight!Theyarerobbersinappearancetoo,sportingatuftofstiffbristles-likeamoustache-betweentheireyes,thataremountedprominentlyontheirhead.Infact,theterm‘mystax’usedtodescribethesebristlesisderivedfromtheGreekwordmeaning‘moustache’or‘upperlip’.Thesecosmopolitanfliesenjoyaworldwidedistribution,butarecommonintropicalandsubtropicalareas,andabundantindryandsunnyaridorsemi-aridzones.
Robberfliescanveryeasilybeidentifiedbytheirlongslenderbodies,withthetipsoftheirabdomensvisiblebeyondthefoldedwings.Themystaxisunmistakable,andtheheadandthoraxishairy.Becauseoftheirlongtaperingabdomen,combinedwithbrightlycoloured–black,grey,redoryellow-patterns,theyareoftenmistakenforwasps.Someofthemwithstout,hairybodies,mimicbees;whileotherswithslender,lithebodies,imitatedamselflies.Asyoucansee,theserobbershavemasteredtheartofdisguisetoo!Theirperchisanotherwayofidentifyingthesefliesinahabitat.Robbersliketoperchonthetopmostendofaplantwaitingtoseizeprey.
Robbersinjectcapturedpreywithsalivacontainingneurotoxicandproteolyticenzymes,killingthem.Bothadultandjuvenilerobberfliespreyonawidevarietyofinsects,thusservingtheimportantecologicalfunctionofkeepingacheckontheinsectfaunainanyarea.
Soldierfliesarediverseintheirhabitsandfoodpreferences,butaremainlyrecognisedbytheiruniquewingvenation.Somesoldiersarepollinators;someassistwithforensics;othersarehelpfulincompostingwaste;whileafewofthemarepredatory.Thebrightlycolouredonesresemblewaspsandbees.Soldiersmaybesaprophagus,myophagousorpredatory;andaregenerallyfoundclosetoaquatichabitatsinwhichtheirlarvaedevelop.Thesefliesarenotawidelyresearchedgroup,exceptHermetiaillucens,whichiscommonlycalledtheblacksoldierfly.Weshalllookatthisflyagain,inthenextsection.
D.FliesinComposting:Theblacksoldierfly,Hermetiaillucens,isnowbeingextensivelyusedtocompostwastes.However,thisprocessisyettofindwiderapplicationinIndia,andiscurrentlybeingpractisedonlybyafewresearchersinPune.
Long-legged flies
Green Soldier Fly
Small Soldier Fly
Black Soldier Fly
Soldier Fly Crane Fly
Mating Robber Flies
Thecompostpitinmybackyardhasblacksoldierflies.Thephotogivenhereisofoneofthemhelpingdecomposewaste,alongwithotherorganisms.
E.FliesinScientificResearch:Fruitflieshavebeeninourlaboratoriesfordecadesnow,andcontinuetoplayawell-knownandextensivelydocumentedroleinoureffortstounderstandgeneactionandinheritancemechanisms.
Whatislesswell-knownistheroleoffliesinsomeotherkindsofexperiments.In2007,forexample,someresearchersatHarvardUniversitybuiltaroboticfly.Weighing60mg,andwithawingspanof3cm,thislife-likeflywasmodelledtoimitatethemovementsofarealfly.Madeofultra-thincarbonfibre,theroboticflyhasawingbeatof110beats/second.Thiseffortisthefirststepto
98I WONDER... MAGAZINE SUBHEAD
GeethaIyerisanAuthorandIndependentconsultantworkinginthetwinfieldsofEducationandEnvironment.Shehaswrittenextensivelyontopicsineducation,environmentandNaturalHistory.DrIyercanbereachedatbrownfishowl@yahoo.co.uk
buildingflyinginsectsthatcanbemountedwithsensors,tofunctionasspies.‘Flyonthewall’willsoonbecomeareality,andnotjustbeafancyidiom,orsoitseems.Armylaboratorieshavedefinitelyshownagreatinterestintheseflyspies.
F.FliesandSoilFertility:Imagineanoversizedmosquito-thatiswhatacraneflyortipulidfly,belongingtothefamilyTipulidae,lookslike.But,thesimilarityendswiththeirappearance.Thesegentlefliesnotonlydonotbite;adultsdonotfeedatall!Adultfliesliveforabout10to15days.Femalesemergefromtheirpupawithmatureova.Theyseekoutmates,andsoonafter,laytheireggsonmoistsoil,orsometimes,onthesurfaceofwater.Astheyfeed,theirlarvaehelpdecomposeorganicmatter,andincreasemicrobialactivityinthesoil.Theyare,therefore,veryusefulinasoilecosystem,keepingthesoilfertilethroughtheiractivities.
Theyareveryeasilyrecognizedbytheirslenderelongatedbodiesandlegs.Theirlegs,especially,arequitelong.Althoughtheyarefoundworldwide,theirdiversityisgreatestinthetropics.Easilyattractedtolight,youcanseethemclingingtothewallswiththeirlonglegsspreadout.Orifyouareoutforawalkinthemorning,theycanbeseenrestingonleaves.Interestingly,cranefliescanoftenbeseenwalkingaseasilyasflying!
FliesinScienceClassrooms
Thehousefly,nodoubt,willcontinuetobetheonethatstudentswillencountermostoftenintheirlessons.Whynotmakeitinterestingtoteachalessononthemouthpartsofaflyinadifferentway?Mouthpartsareforfeeding,andwhatbetterwaytolearnaboutthemthantoactuallyseeaflyfeeding.
Howdoesonedothis?Tobeginwith,onewould,ofcourse,needalivefly.And,manipulatingasmallflycanbeatrickyaffair!Butwithalittlebitofpractice,youshouldbefine!It’sonlyfairtomentionthatthisinvestigationcallsforalotofpatienceandtime,butiswellworththetimespentindoingit,forIassureyouthatalotmorethanhowaflydetectsorfeedsislearntthroughsuchactivities.Forexample,thisinvestigationwillshowthatfliestastewiththeirfeet!
Leavesomeoverripebananaoramangoaround,andverysoonyouwillseemanyhousefliespayingthemavisit.Useasmallteastraineroramoistclothtotrapafewoftheseflies,andstore
theminsideadrytransparentjar.Donotkeeptoomanyoftheminsideonejar.
Thenextfewstepsarethetrickyones.Takethreeglassslides,andnumberthem1,2and3.Putafewdropsofwateron1and,2,andsugarsolutionon3.
Thestepfollowingthishastobedoneveryquickly.SmearsomeFevicol(notFeviquick,pleasenote)onyourforefinger,openthejarwiththetrappedflies,andtouchthethoraxofthenearestflywithyourforefinger.Theflywillgetstucktoyourfinger.Holditgentlywithyourfingersinsuchawaythatbothitswingsremainfoldedonitsback.Don’tworry-attheendofthisexperiment,youcanreleasetheflybywashingyourforefingerinwater.Theflywillbewetforsometime(youcangentlydabitdrywithacloth),butwillsoondryitselfout,andfly.
Theflywillbestressedbecauseofitscaptivity.Whenyougentlyloweritclosetothewater-droponslide1,youcanactuallyseeitsproboscispopoutofitsheadtodrinkwater.Whenithasfinisheddrinkingwater,takeitofffromslideone,andnowloweritontothewaterdropinslidetwoinsuchawaythatitsfeettouchthewater.Doyouseetheprobosciscomingdown?
Now,repeatthesamewithslidethree,andyouwillseethatassoonasitslegstouchthesugarsolution,outpopsthefly’sproboscistofeedonthesugarsolution.Youmaynowtrydifferentkindsoffood,andinvestigatethefly’sfeedingpreferencesorhowmuchitneedstofeedon,etc.Seeinganinsectfeedcreatesanactivelearningatmosphereintheclassroom,whichcanthenbefollowedupwithanatomicaldetailsunderthemicroscope.
Conclusion
Thisisbutasmallintroductiontoafewfamiliesoffliesthatmaybefoundmorecommonlyinourhumanenvironments,andarebigenoughtoberecognised.Morethan1,60,000speciesofflies,andstillcounting-makesmeagreewithNash,whenhesays:
GodinhiswisdomMadetheflyAndthenforgotTotelluswhy
–OgdenNash
References
1.Oneproboscis,twotasks:Adaptationstoblood-feedingandnectar-extractinginlong-proboscidhorseflies(Tabanidae,Philoliche).KarolyiaFlorianetal.ArthropodStructure&Development,Vol.43:Issue5,Sept2014:403-413.
2.Theuseofinsectsinforensicinvestigations:Anoverviewonthescopeofforensicentomology.Josephetal.JournalofForensicDentalSciences,Vol.3(2);Jul-Dec2011:89-91.URL:www.ncbi.nlm.nih.gov/pmc/articles/PMC3296382/
3.Lordsoftheflies:theinsectdetectives.JonHenley.TheGuardian:ForensicScience.Sep23,2010.URL:http://www.theguardian.com/science/2010/sep/23/flies-murder-natural-history-museum.
4.Courtshipinlong-leggedflies(Diptera:Dolichopodidae):functionandevolutionofsignals.MartinZimmer,OlafDiestelhorst,andKlausLunau.BehavioralEcology,Vol.14,No.4:526–530.URL:http://beheco.oxfordjournals.org/content/14/4/526.full.pdf
5.RobberFlies(Asilidae).FritzGeller-Grimm,TorstenDikow&RobertJ.Lavigne.URL:http://www.geller-grimm.de/asilidae.htm.
6.OccurrenceofBlackSoldierFlyHermetiaillucens(Diptera:Stratiomyidae)inBiocompost.GujarathiGayatriR.andPejaverMadhuriK.ResearchJournalofRecentSciences,Vol.2(4),April(2013):65-66.URL:http://www.isca.in/rjrs/archive/v2/i4/9.ISCA-RJRS-2012-469.pdf.
7.Blacksoldierflyfarming.URL:http://www.blacksoldierflyfarming.com/.
98I WONDER... MAGAZINE SUBHEAD
GeethaIyerisanAuthorandIndependentconsultantworkinginthetwinfieldsofEducationandEnvironment.Shehaswrittenextensivelyontopicsineducation,environmentandNaturalHistory.DrIyercanbereachedatbrownfishowl@yahoo.co.uk
buildingflyinginsectsthatcanbemountedwithsensors,tofunctionasspies.‘Flyonthewall’willsoonbecomeareality,andnotjustbeafancyidiom,orsoitseems.Armylaboratorieshavedefinitelyshownagreatinterestintheseflyspies.
F.FliesandSoilFertility:Imagineanoversizedmosquito-thatiswhatacraneflyortipulidfly,belongingtothefamilyTipulidae,lookslike.But,thesimilarityendswiththeirappearance.Thesegentlefliesnotonlydonotbite;adultsdonotfeedatall!Adultfliesliveforabout10to15days.Femalesemergefromtheirpupawithmatureova.Theyseekoutmates,andsoonafter,laytheireggsonmoistsoil,orsometimes,onthesurfaceofwater.Astheyfeed,theirlarvaehelpdecomposeorganicmatter,andincreasemicrobialactivityinthesoil.Theyare,therefore,veryusefulinasoilecosystem,keepingthesoilfertilethroughtheiractivities.
Theyareveryeasilyrecognizedbytheirslenderelongatedbodiesandlegs.Theirlegs,especially,arequitelong.Althoughtheyarefoundworldwide,theirdiversityisgreatestinthetropics.Easilyattractedtolight,youcanseethemclingingtothewallswiththeirlonglegsspreadout.Orifyouareoutforawalkinthemorning,theycanbeseenrestingonleaves.Interestingly,cranefliescanoftenbeseenwalkingaseasilyasflying!
FliesinScienceClassrooms
Thehousefly,nodoubt,willcontinuetobetheonethatstudentswillencountermostoftenintheirlessons.Whynotmakeitinterestingtoteachalessononthemouthpartsofaflyinadifferentway?Mouthpartsareforfeeding,andwhatbetterwaytolearnaboutthemthantoactuallyseeaflyfeeding.
Howdoesonedothis?Tobeginwith,onewould,ofcourse,needalivefly.And,manipulatingasmallflycanbeatrickyaffair!Butwithalittlebitofpractice,youshouldbefine!It’sonlyfairtomentionthatthisinvestigationcallsforalotofpatienceandtime,butiswellworththetimespentindoingit,forIassureyouthatalotmorethanhowaflydetectsorfeedsislearntthroughsuchactivities.Forexample,thisinvestigationwillshowthatfliestastewiththeirfeet!
Leavesomeoverripebananaoramangoaround,andverysoonyouwillseemanyhousefliespayingthemavisit.Useasmallteastraineroramoistclothtotrapafewoftheseflies,andstore
theminsideadrytransparentjar.Donotkeeptoomanyoftheminsideonejar.
Thenextfewstepsarethetrickyones.Takethreeglassslides,andnumberthem1,2and3.Putafewdropsofwateron1and,2,andsugarsolutionon3.
Thestepfollowingthishastobedoneveryquickly.SmearsomeFevicol(notFeviquick,pleasenote)onyourforefinger,openthejarwiththetrappedflies,andtouchthethoraxofthenearestflywithyourforefinger.Theflywillgetstucktoyourfinger.Holditgentlywithyourfingersinsuchawaythatbothitswingsremainfoldedonitsback.Don’tworry-attheendofthisexperiment,youcanreleasetheflybywashingyourforefingerinwater.Theflywillbewetforsometime(youcangentlydabitdrywithacloth),butwillsoondryitselfout,andfly.
Theflywillbestressedbecauseofitscaptivity.Whenyougentlyloweritclosetothewater-droponslide1,youcanactuallyseeitsproboscispopoutofitsheadtodrinkwater.Whenithasfinisheddrinkingwater,takeitofffromslideone,andnowloweritontothewaterdropinslidetwoinsuchawaythatitsfeettouchthewater.Doyouseetheprobosciscomingdown?
Now,repeatthesamewithslidethree,andyouwillseethatassoonasitslegstouchthesugarsolution,outpopsthefly’sproboscistofeedonthesugarsolution.Youmaynowtrydifferentkindsoffood,andinvestigatethefly’sfeedingpreferencesorhowmuchitneedstofeedon,etc.Seeinganinsectfeedcreatesanactivelearningatmosphereintheclassroom,whichcanthenbefollowedupwithanatomicaldetailsunderthemicroscope.
Conclusion
Thisisbutasmallintroductiontoafewfamiliesoffliesthatmaybefoundmorecommonlyinourhumanenvironments,andarebigenoughtoberecognised.Morethan1,60,000speciesofflies,andstillcounting-makesmeagreewithNash,whenhesays:
GodinhiswisdomMadetheflyAndthenforgotTotelluswhy
–OgdenNash
References
1.Oneproboscis,twotasks:Adaptationstoblood-feedingandnectar-extractinginlong-proboscidhorseflies(Tabanidae,Philoliche).KarolyiaFlorianetal.ArthropodStructure&Development,Vol.43:Issue5,Sept2014:403-413.
2.Theuseofinsectsinforensicinvestigations:Anoverviewonthescopeofforensicentomology.Josephetal.JournalofForensicDentalSciences,Vol.3(2);Jul-Dec2011:89-91.URL:www.ncbi.nlm.nih.gov/pmc/articles/PMC3296382/
3.Lordsoftheflies:theinsectdetectives.JonHenley.TheGuardian:ForensicScience.Sep23,2010.URL:http://www.theguardian.com/science/2010/sep/23/flies-murder-natural-history-museum.
4.Courtshipinlong-leggedflies(Diptera:Dolichopodidae):functionandevolutionofsignals.MartinZimmer,OlafDiestelhorst,andKlausLunau.BehavioralEcology,Vol.14,No.4:526–530.URL:http://beheco.oxfordjournals.org/content/14/4/526.full.pdf
5.RobberFlies(Asilidae).FritzGeller-Grimm,TorstenDikow&RobertJ.Lavigne.URL:http://www.geller-grimm.de/asilidae.htm.
6.OccurrenceofBlackSoldierFlyHermetiaillucens(Diptera:Stratiomyidae)inBiocompost.GujarathiGayatriR.andPejaverMadhuriK.ResearchJournalofRecentSciences,Vol.2(4),April(2013):65-66.URL:http://www.isca.in/rjrs/archive/v2/i4/9.ISCA-RJRS-2012-469.pdf.
7.Blacksoldierflyfarming.URL:http://www.blacksoldierflyfarming.com/.
