tpo1-34解析包-閱讀tpo9reading1譯文

西北海岸的ColonizingtheAmericasviatheNorthwest西北海岸的IthaslongbeenacceptedthattheAmericaswerecolonizedbyamigrationofpeoplesfromAsia,slowlytravelingacrossalandbridgecalledBeringia(nowtheBeringStraitbetweennortheasternAsiaandAlaska)duringthelastIceAge.■Thewatercrafttheoryaboutthemigrationwasthataround11,000-12,000yearsagotherewasanice-freecorridorstretchingfromeasternBeringiatotheareasofNorthAmerica,southofthegreatnorthernglaciers.Itwasthemidcontinentalcorridorbetweentwomassiveicesheets—theLaurentidetotheeastandtheCordillerantothewest—thatenabledthesouthwardmigration.■Butbeliefinthisice-freecorridorbegantocrumblewhenpaleoecologistGlenMacDonalddemonstratedthatsomeofthemostimportantradiocarbondatesusedtosupporttheexistenceofanice-freecorridorwereincorrect.Hepersuasivelyarguedthatsuchanice-freecorridordidnotexistuntilmuchlater,whenthecontinentalicebeganitsfinalretreat.■這種觀(guān)念們接受很長(zhǎng)時(shí)間了：美洲被一群來(lái)自亞洲的殖民著，他們?cè)谏弦粋€(gè)時(shí)代緩慢地了一個(gè)叫做白令的大陸橋（現(xiàn)在白令海峽位于東北亞和阿拉斯加之間。關(guān)于這些遷徙的第一個(gè)水路理論表明，大概在11,000南部。正是這個(gè)連在兩個(gè)巨大冰床（東邊的LaurentideCordilleran）之關(guān)于不凍走廊的理論也就了。他令人信服地，那樣的不凍走廊直到很久Supportisgrowingforthealternativetheorythatpeopleusingwatercraft,possiblyskinboats,movedsouthwardfromBeringiaalongtheGulfofAlaskaandthensouthwardalongtheNorthwestCoastofNorthAmericapossiblyasearlyas16,000yearsago.ThisroutewouldhaveenabledhumanstoentersouthernareasoftheAmericanspriortothemeltingofthecontinentalglaciers.Untiltheearly1970s,mostarchaeologistsdidnotconsiderthecoastapossiblemigrationrouteintotheAmericansbecausegeologistsoriginallybelievedthatduringthelastIceAgetheentireNorthwestCoastwascoveredbyglacialice.IthadbeenassumedthattheiceextendedwestwardfromtheAlaskan/Canadianmountainstotheveryedgeofthecontinentalshelf,theflat,submergedpartofthecontinentthatextendintotheocean.ThiswouldhavecreatedabarrieroficeextendingfromtheAlaskninsula,throughtheGulfofAlaskaandsouthwardalongtheNorthwestCoastofNorthAmericatowhatistodaythestateof另外一種理論認(rèn)為，可能早在16,000年前，人們就使用船只，也許是那種獸美洲南部地區(qū)。直到20世紀(jì)70年代早期，大部分考古學(xué)家都不認(rèn)為海岸是進(jìn)入 ThemostinfluentialproponentofthecoastalmigrationroutehasbeenCanadianarchaeologistKnutFladmark.Hetheorizedthatwiththeuseofwatercraft,peoplegraduallycolonizedunglaciatedrefugesandareasalongthecontinentalshelfexposedbythelowersealevel.Fladmark'shypothesisreceivedadditionalsupportfromthefactthatthegreatestdiversityinNativeAmericanlanguagesoccursalongthewestcoastoftheAmericans,suggestingthatthisregionhasbeensettledthelongest.海岸路線(xiàn)的最有的支持者是考古學(xué)家KnutFladmark。他這表明這個(gè)地區(qū)是人類(lèi)時(shí)間最早的。這一事實(shí)也支持了Fladmark的假設(shè)。Morerecentgeologicstudieseddeglaciationandtheexistenceofice-freeareasthroughoutmajorcoastalareasofBritishColumbia,Canada,by13,000yearsago.ResearchnowindicatesthatsizableareasofsoutheasternAlaskaalongtheinnercontinentalshelfwerenotcoveredbyicetowardofthelastIceAge.Onestudysuggeststhatexceptfora250-coastalareabetweensouthwesternBritishColumbiaandWashingtonState,theNorthwestCoastofNorthAmericawaslargelyfreeoficebyapproximay16,000yearsago.Vastareasalongthecoastmayhavebeendeglaciatedbeginningaround16,000yearsago,possiblyprovidingacoastalcorridorforthemovementofplants,animals,andhumanssometimebetween13,000and14,000yearsago.最近的地質(zhì)研究記載了13,000年前在的不列顛哥倫比亞省主要之外，的西北海岸在大概16,000年之前都沒(méi)有冰存在。沿海的遼闊地區(qū)的冰川在大約16,000年前開(kāi)始融化，這就13,000年前到14,000年前的某一段時(shí)Thecoastalhypothesishasgainedincreasingsupportinrecentyearsbecausetheremainsoflargelandanimals,suchascaribouandbrownbears,havebeenfoundinsoutheasternAlaskadatingbetween10,000and12,500yearsago.Thisisthetimeperiodinwhiostscientistsformerlybelievedtheareatobeinhospitableforhumans.Ithasbeensuggestedthatiftheenvironmentwerecapableofsupportingbreedingpopulationsofbears,therewouldhavebeenenoughfoodresourcestosupporthumans.FladmarkandothersbelievethatthehumancolonizationofAmericaoccurredbyboatalongtheNorthwestCoastduringtheverylateIceAge,possiblyasearlyas14,000yearsago.Themostrecentgeologicevidenceindicatesthatitmayhavebeenpossibleforpeopletocolonizeice-freeregionsalongthecontinentalshelfthatwerestillexposedbythelowersealevelbetween13,000and14,000yearsago.的遺跡出現(xiàn)在阿拉斯加?xùn)|南10,00012,500年14,000年以前。的地質(zhì)資料表明：在13,00014,000年前，人們可能在因較低的海平面而露的大陸架沿岸的無(wú)冰區(qū)域殖民。Thecoastalhypothesissuggestsaneconomybasedonmarinemammal