If Mary Beard is right, what's happened to the DNA of Africans ...

Roman Britain was indeed a multi-ethnic society, which included ... of a black Roman soldier in the detachment building Hadrian's Wall, ... SkiptomaincontentSkiptonavigationAdvertisementNewsOpinionSportCultureLifestyleShowMoreShowMoreNewsWorldnewsUKnewsCoronavirusClimatecrisisEnvironmentScienceGlobaldevelopmentFootballTechBusinessObituariesOpinionTheGuardianviewColumnistsCartoonsOpinionvideosLettersSportFootballCricketRugbyunionTennisCyclingF1GolfUSsportsCultureBooksMusicTV&radioArt&designFilmGamesClassicalStageLifestyleFashionFoodRecipesLove&sexHealth&fitnessHome&gardenWomenMenFamilyTravelMoneyMakeacontributionSubscribeSearchjobsHolidaysDigitalArchiveGuardianPuzzlesappGuardiancontentlicensingsiteTheGuardianappVideoPodcastsPicturesNewslettersToday'spaperInsidetheGuardianTheObserverGuardianWeeklyCrosswordsFacebookTwitterSearchjobsHolidaysDigitalArchiveGuardianPuzzlesappGuardiancontentlicensingsiteWorldUKCoronavirusClimatecrisisEnvironmentScienceGlobaldevelopmentFootballTechBusinessObituariesThepastandthecuriousRomanBritainIfMaryBeardisright,what'shappenedtotheDNAofAfricansfromRomanBritain?Therearemanyreasonswhyageneticlegacymightnotbeseenincontemporarypopulations–MaryBeardwasrighttodefendtheBBC’scartoonIfancientDNAhastaughtusanything,it’sthatyoucannotuniversallyreconstructpopulationhistoriesonthebasisofcontemporarypatternsofgeneticdiversity.Photograph:BBCIfancientDNAhastaughtusanything,it’sthatyoucannotuniversallyreconstructpopulationhistoriesonthebasisofcontemporarypatternsofgeneticdiversity.Photograph:BBCJenniferRaffWed9Aug201711.40BSTLastmodifiedonWed1Jul202017.55BSTIfyouhavebeenonsocialmediaatallforthelastcoupleofweeks,youarelikelyawareofwhatmaybeoneofthesilliestcontroversiesever:whetheradark-skinnedmanshouldbepresentinaBBCcartoonforchildrenaboutlifeinRomanBritain.Criticshaveraisedmultipleobjectionsonthetheme:whetherdarkskinwas“typical”(eventhoughnoscholarhasclaimedthatitwas),whatpercentageofthepopulationmustbenonwhitebeforeitcanbecalled“diverse,”andstatementslikethis.Peopleupsetbythecartoonhaveshiftedgoalposts,ignoredordistortedcogentarguments,andmockedtheknowledgeofexperts.It’sbeenugly,particularlytheattacksonProfessorMaryBeard,arenownedclassicist.ThethemeunitingalltheseeffortsisrhetoricaccusingscholarsandtheBBCof“rewritinghistory”whilesimultaneouslyprojectingcontemporarynotionsofracebackwardsintimeontoasocietythatdidn’tsharethem.MaryBeardisright–‘Romans’couldbefromanywhere,fromCarlisletoCairoReadmoreFirst,let’sgetthisoutoftheway.Whetherornotthiscartoonfamilywasexceptional(andasclassicistDr.MatthewNichollshaspointedout,thefactthatthemotherofthefamilywasliterateisperhapsjustasexceptionalasthefather’sskintone)isbesidethepoint.RomanBritainwasindeedamulti-ethnicsociety,whichincludedpeoplefromAfrica,andmostlyfromNorthernAfrica.TheexactpercentagesofAfricanRomanswithinthelargerpopulationisunknown,andprobablyvariedfromplacetoplace.Multiplelinesofindependentevidence,includingisotopicanalysesofteethandbones,osteology,archaeology,andhistoricaldocumentsmakethisclear.Whilemostoftheisotopicevidencelocatestheseindividuals’birthplacestoNorthAfrica,therearealsowrittenaccountsofpeoplefromfurthersouth,asDr.Nichollsnotes: “TheinternetdiscussionwasparticularlypromptedbytheappearanceofablackRomansoldierinthedetachmentbuildingHadrian’sWall,butinfactthereisanancientaccountofpreciselythis–theemperorSeptimiusSeverus(himselfinfactanAfrican,fromLibya)wasinspectinghistroopsontheWallwhenoneofthegarrison’swell-knownjokers,an‘Ethiopian’,offeredhimagarland. Severuswasstartledbytheapparentomen,associatingthesoldier’sblackcolourasaportentofhisownimminentdeath,butno-oneseemstohavebeenparticularlysurprisedatthepresenceofan‘Ethiopian’(thatis,ablackAfrican)atthenorthernedgeoftheRomanempire(Hist.Aug.Severus22).” Infact,BeardsuggeststhattheimageintheBBCcartoonwaslooselybasedonanotherhistoricalfigure,theAlgerianQuintusLolliusUrbicus.Herpoint,madepatientlyagainandagain,isthatwedon’tknowtheexactshadeofhisskin,orwhetheritwasaccuratelyreflectedinthecartoon–thatitwasmostlikelyanartisticchoicedesignedtomakethepointtochildrenthattherewere“vastdisparitiesinRomanBritaininethnicityandculture”,andthatseeingsuchaperson“wouldbeunsurprisinginanurbancontext.”Iamnotinterestedingoingthroughthewholestory(youcanreadasummaryhere),noramIinterestedinlitigatingwhetherornotit’s“fair”toportrayachildren’scartooncharacterwithdarkskin,butonepointthathasbeenraisediswellworthaddressinghereatThePastandtheCurious.Geneticsstudieshavebeenhelduptriumphantlyasarefutationtothe“fuzzy”humanitiessortofapproach.Thisargumentgoes:there’slittleornoevidenceofAfricanDNAlineages(evennorthernAfricans,whowouldbepredictedtomorecloselyresembleEuropeansduetoalonghistoryofgeneflowthroughtheMiddleEast)incontemporaryBritishpopulations,sothereforehistoriansarewrong.IftherewereAfricansinRomanBritain,whyisn’tthereageneticlegacyfromtheseindividualsamongpresent-dayinhabitantsofBritain?It’safairquestion,andonewhichhasseveralpotentialanswers:1.GeneticdriftmayhaveerasedtheirtracesfromthepopulationPopulationsarenotstatic:thegeneticmakeupofaregionoftenchangesovertimeduetoevolutionaryforceslikemigrationandgeneticdrift.Geneticdriftchangesthefrequencyofalleles(formsofagene)randomlywithinapopulationovertime.Uniparentalmarkers,likemitochondrial(onlymaternallyinherited)andYchromosome(onlypaternallyinherited)DNAareparticularlyaffectedbygeneticdrift.IfamitochondrialorYchromosomelineagewasrareinapopulation,it’slikelythatitwouldhavedisappearedfromthepopulationovertimeandnotbeseenincontemporaryinhabitantsoftheregion.Weseemanyexamplesofthelossofancientlineagesindifferentregionsthroughouttheworld.Allelescanalsoincreaseinfrequency–theycanberareinthepast,andplentifulnow,allwithoutneedingtoinvokenaturalselection…justchance.2.Theymaynothaveleftnumerous(orany)descendantsinthepopulationThereareahostofotherfactorsinadditiontogeneticdriftthatcanalsoaffectthegeneticcompositionofaregionovertime,mostparticularlythevaryingwaysinwhichpeopleinteractwhentheycomeintocontactwitheachother.Forexample,ancestryfrommultiplepopulationsofinvaderscanbeseenincontemporaryBritishgenomes.ButasgeneticistDrAdamRutherfordpointsoutinhisbook“ABriefHistoryofEveryoneWhoEverLived”,notallofthem: “YetthereisvirtuallynotraceoftheDanesintheBritishgenome.ComparedtotheAnglesandSaxonsandeventheNorwegians’geneticlegacyinthenorthofScotland,there’sanabsenceofDanishDNAdespitealongadventurehere.(pp115-116).” Therearesimilarcasesallovertheworld,includingfrommyownareaofresearch,theAmericas.ThereisextremelywelldocumentedevidenceofaNorseoccupationatL’AnseauxMeadows,asiteinNewfoundlandaround1000AD,yetnogenetictracesoftheNorsecanbefoundineithercontemporaryorancientNativeAmericanpopulations.Thismaymeanthattherewasnoadmixture(mating)takingplacebetweenNorseandindigenouspopulations,orperhapsthatitwasonsuchasmallscalethattraceswereerasedovertime.Thegeneticdatadoesn’tshowtheNorseintheAmericas,butweareprettyconfidenttheywerethere.Doesthatmeanthatgeneticdataorarchaeologyareanymoreorlessimportantassourcesofinformationaboutthepast?Theskeletonofayoungwomaninherearly20’soflateRomanLondon,datingfromthefirsthalfofthe4thCentuaryADfoundinSpitalfieldsMarketredevelopmentsiteintheCityofLondonPhotograph:SeanDempsey/PA3.TheymaysimplynothavebeensampledyetIfancientDNAhastaughtusanything,it’sthatyoucannotuniversallyreconstructpopulationhistoriesonthebasisofcontemporarypatternsofgeneticdiversity.Togetatacomprehensiveunderstandingofgeneticdiversityofindividualsfromapastpopulationatagiventimeperiod,youreallyneedtodirectlycharacterizetheirgenomes.TounderstandthegeneticdiversitypresentinRomanBritain,thiswillneedtobedoneonamuchwiderscalethanpresent,acrossbothtimeandspace,andwewillneedtotargetspecificindividualssuspectedofbeingnon-localinordertoobservelineagespresentinthepastatrarefrequencies.Furthermore,onehastobeverycarefulaboutdesigningastudyintendedtoaccuratelycharacterizegeneticvariationinanentirepopulation;youcan’tjustsequenceDNAfromeliteburials,forexample,oryoumaygetanincrediblybiasedperspectiveofthewholepopulationThesetypesofancientDNAsurveysarebeingdoneinBritain,buttheyaren’tcomprehensiveandmuchmoreworkremainstobedonebyfutureinvestigatorsFramingthisissueasadebatebetweenhardscienceandfuzzyhumanitiesissimplynonsense.Reconstructingthepastisamultidisciplinaryeffort,andIcan’tthinkofasinglegeneticistwhowouldn’tcandidlyadmittomanylimitationsinourapproaches.Togetaroundtheselimitations,andtoimprovethecollectionandinterpretationofourdata,weworkcloselywithcollaboratorsinotherdisciplines:archaeologists,linguists,osteologists,specialistsinstableisotopeanalysis,andyes,evenhistorians.Perhapsinsteadoffussingaboutwhethercartooncharactersconformtoourbeliefsabouthowtheancientworldshouldhavebeen,ourenergieswouldbebetterspentinlearningmoreabouthowitactuallywas.TopicsRomanBritainThepastandthecuriousGeneticsMaryBeardBiologyBBCblogpostsReusethiscontentMoreonthisstoryMoreonthisstoryNotabouncycastle:Hadrian’sWallfortrebuiltinwildcolourRomansventureddeeperintoWalesthanthought,roaddiscoveryshowsLavishRomanmosaicisbiggestfoundinLondonfor50yearsShackledskeletonidentifiedasrareevidenceofslaveryinRomanBritainRomansiteuncoveredinScarboroughhailedasfirstofitskindinUKStunningdarkagesmosaicfoundatRomanvillainCotswoldsHadrian’sWalldigrevealsoldestChristiangraffitionchalicePracticaljokeortoy?Leather‘mouse’showsRomans'playfulsideAmateurarchaeologistsredrawmapofRomanBritain–fromhomeMostpopularMostpopularWorldUKCoronavirusClimatecrisisEnvironmentScienceGlobaldevelopmentFootballTechBusinessObituaries