Science & Technology

The Younger Dryas and Late Pleistocene Peoples of the Great Lakes Region.

Description
The Late Pleistocene archaeological record of the Great Lakes drainage area shows that there were several, albeit spatially variable, changes in that record in a time period corresponding to the Younger Dryas (YD) climatic reversal at ca.
Published
of 12
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
  The Younger Dryas and Late Pleistocene peoples of the Great Lakes region Christopher J. Ellis a , * , Dillon H. Carr b , Thomas J. Loebel c a Department of Anthropology, Social Science Centre, University of Western Ontario, London, Ontario N6A 5C2, Canada b Department of Anthropology, Michigan State University, 355 Baker Hall, East Lansing, MI 48824, USA c CAGIS Archaeological Consulting Services, Department of Anthropology, University of Illinois at Chicago, 1007 W. Harrison St., Chicago, IL 60607, USA a r t i c l e i n f o  Article history: Available online 16 March 2011 a b s t r a c t The Late Pleistocene archaeological record of the Great Lakes drainage area shows that there wereseveral, albeit spatially variable, changes in that record in a time period corresponding to the YoungerDryas (YD) climatic reversal at ca. 10,800 e 10,000  14 C BP. Notable here are declines in some areas in themobility of Paleoindian groups as measured by distance to the main lithic source employed, declines inthe overall frequency of sites/ 󿬁 ndpots, particularly in the western Great Lakes where some northernareas seem to have been largely abandoned, and an increasing association of occupation locales withglacial lake shores or extensive wetlands left by recently drained glacial lakes. Some of the changes, as inrange mobility, most likely relate to the colonization of new areas rather than directly to the YD.Speci 󿬁 cally, the earliest groups were able to target rich, but widely dispersed, resource locales due to anabsence of competing groups. However, the declines in locale frequencies and shifting distributions of those locales may be due to YD in 󿬂 uence, notably to an eventual drying out of the area that resulted inless productive environments overall and made the lake shores and wetland areas more attractiveenvironmental niches for human occupation.   2011 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction This paper presents an overview of the late Pleistocene prehis-tory, ca. 11,000 to 10,000  14 C BP, of the Great Lakes Region (Fig. 1).The focus is on changes evident in the archaeological record andtheir relationship to climatic/environmental shifts that in turn canberelatedtothetimeoftheYoungerDryasclimaticevent(hereafterYD). Since the1950s there havebeen several attemptstodocumentchanges in the early archaeological record of the vast Great Lakesareaandrelatethesechangestoshiftsinenvironmentalconditions,notably the shift from spruce to pine-dominated vegetation and anaccompanying greater forest closure over time, to the extinction of late Pleistocene fauna, and to changes in the levels of the GreatLakes themselves (e.g., Mason, 1958, 1982:81 e 126; Roosa, 1968;Ritchie, 1969:1 e 30; Fitting, 1970:34 e 63; Dibb, 1985; Shott, 1986;Deller and Ellis, 1988; Deller, 1989; Ellis and Deller, 1997).However, these efforts pre-date any major interest in the YD  per se andtheydidnotrelatetotheeffectsofthatclimaticeventonhumanbehaviourandenvironmentalcopingstrategies.Onenotablerecentexception is Metin Eren (2009), who examined the environmentaland archaeological record for cause and effect relationships withthe YD in the eastern Great Lakes area of Ohio, Ontario, New Yorkand Michigan. In direct contrast to many earlier researchers, Eren(2009) concluded that there were few or no changes in thearchaeological record in YD time; it either had no effects, or alter-natively, the cultural historical constructs, based largely on pointtypologies, are not measuring time changes or do not representa time sequence.The authors believe that the cultural historical  sequence  modelsare generally valid, although anchoring them precisely in time tosome calendrical system is another matter. Moreover,using thosecultural historical models, there are clear suggestions of changes intheGreatLakesareaovertimeinaperiodcorrespondingtotheYDasa whole, although these human responses may vary spatially, asbetween the western and eastern Great Lakes and even at smallerscales. While one can demonstrate such changes, actually relatingthem causally to the YD, except in the broadest possible terms, ismore dif  󿬁 cult. There is not only the problem of a lack of rigoroustemporal controls, controls long-recognized as essential to corre-lating archeological and environmental data (Dincauze, 1981), butalso, and of course, as anthropologists and not environmentaldeterminists,someofthechangesthatoccurredinhumanlifestylesof the area over the 11,000 e 10,000  14 C BP period are not under-standablesolelyintermsofenvironmentalchanges.Theyalsorelateto other variables such as the unusually low population size anddensity in the area during this period of   󿬁 rst sustained human use. *  Corresponding author. Fax:  þ 1 519 661 2157. E-mail address:  cjellis@uwo.ca (C.J. Ellis). Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint 1040-6182/$  e  see front matter    2011 Elsevier Ltd and INQUA. All rights reserved.doi:10.1016/j.quaint.2011.02.038 Quaternary International 242 (2011) 534 e 545  One also needs to ask the more general question why archae-ologists in the Great Lakes should care about the YD in and of itself.The major interest in this climatic event in archaeological circles isbecause of the rapidity with which it occurred, the presumedmagnitude of the change and its environmental effects, and thepossibility it exposed existing populations to severe stress. Anevent of that presumed magnitude would represent an ideal testlaboratory to see how small, low density human populations canrespond to such conditions. In areas to the east of the Great Lakes,there were major and rapid environmental reversals associatedwith the inception of the YD such that some areas were actuallyabandoned or little used by human groups for a substantial period(e.g., Ellis, 2004a). In contrast, in much of the Great Lakes area itseems to have taken some time for the climatic effects of the YD tohave any realon thegroundenvironmental effects. Indeed,in someareas, such as the eastern Great Lakes the YD may have actuallyprolonged existing environmental conditions. Most certainly, inmuch of the area there is no evidence of abrupt changes in envi-ronments at the scale of day to day living, and certainly no climaticreversals of a scale and severity that would have required imme-diate and very rapid responses. The people of the Great Lakes wereresponding to changes but, and in agreement with Meltzer andHolliday (2010), it is not sure there were changes on the groundthat were unusual or different from many other periods of humanprehistory. 2. Temporal frameworks In terms of the YD itself, there are several age estimates andtherehasbeenatendencyamongpaleoenvironmentalspecialiststoround off the age of the event and begin it 11,000  14 C BP or earlier.However, based upon the latest improved estimates fromGreenland ice cores, the Greenland Ice Core Chronology 2005GICC05 (Rasmussen et al., 2006), the YD did not begin until about12,900 e 12,800calBP,orabestguessofafterabout10,900to10,800 14 C BP, and that it ended around 11,500 cal BP or 10,000  14 C BP.In archaeological terms, analysis relies largely on a temporalsequence based on several well-de 󿬁 ned stone point forms or typesknown from the region. Insights into the relative chronology of thesepointformsare basedongeochronological controlsandafewradiocarbon dates within the area as well as dates fromsurrounding regions. This information indicates an overall agerange from ca.11,000 to just after 10,000 14 C BP. In addition, withinthe broad time limits inferred from such chronological controlswell-accepted relative methods of archaeological age estimationusing artifactual data allowsome re 󿬁 nementof temporalorderingsin certain sub-regions such as the eastern Great Lakes (Deller andEllis,1988,1992a; Ellis and Deller,1997:5 e 10).Across the whole Great Lakes, the earliest assemblages havepoints that, although sometimes affected by raw materialconstraints, tend to be large and parallel-sided and have beenassigned various names such as Clovis, Gainey, Enterline andRemington or hybrid designations like Clovis/Gainey or Gainey/Clovis (Witthoft, 1952; McNett, 1985:88 e 89; Storck, 1988; Dellerand Ellis, 1992a; Stoltman, 1993; Brose, 1994:65 e 66; Amick et al.,1997; Gramly, 1999; Morrow and Morrow, 2003; Loebel, 2005).These items are termed  “ Clovis-like ”  here, and they are mostsimilar as a whole to classic western Clovis points. These similari-ties suggest they date early in the sequence and selective datesfromwithin the area of about 10,900  14 C BP, notably from SheridanCave (Waters et al., 2009) and Paleo Crossing (Brose, 1994) in northern Ohio, and from areas just to the east such as Shawnee-Minisinkin Pennsylvania (Watersand Stafford, 2007), suggest touspeople had penetrated the area by that time (Fig. 2). When theClovis-like era ended is not clear cut. Loebel (2005) has suggestedthat in areas such as Wisconsin the occupation ends at ca. 10,800 14 C BP or coincident with the beginning of the YD climatic interval.It is still plausible, although far from demonstrated (Mason, 1997;Amick et al., 1999; Loebel, 2005:12 e 13), that use of presumedlater Clovis-like variants such as Gainey lasted some years later(Morrow and Morrow, 2003:156), or into the early part of the YD,and this is suggested in Fig. 2.After the Clovis-like points, all indications are that the repre-sentation of point styles varies across the region from west to eastwith LakeMichigana convenientdividing point (Fig.1). Focusing inon the western Great Lakes, Clovis-like assemblages are followed Fig.1.  Map of Great Lakes Area. Thick black line denotes western and eastern Great lakes using Lake Michigan as a convenient boundary. Location of Stotzel-Leis, Ohio, pollen siteshown. C.J. Ellis et al. / Quaternary International 242 (2011) 534 e 545  535  by forms better known and dated on the Plains tothe west, notablyFolsomandAgateBasin(Fig.2).PlainsFolsomseemssecurelydatedto between ca.10,800 and 10,300 14 C BP (Fiedel,1999) but if Clovis-like forms like Gainey lasted longer in the Great Lakes region, theFolsom occupation may begin later (Fig. 2). In the west, strati-graphically later Agate Basin materials date ca. 10,200 to 9800  14 CBP (Frison, 1991). Other forms such as Hi-Lo (Fitting, 1963), more characteristic of areas farther east, do occur in limited areas nearLake Michigan, and given their resemblances to Dalton and the factsome are essentiallyside-notched, theyarebelieved to datearound10,000  14 C BP (Ellis, 2004b) In the eastern Great Lakes, Folsom is absent but forms withsimilar technologies, and of presumed similar Middle Paleoindianages, notably Barnes (Roosa, 1965) and Crow 󿬁 eld (Deller and Ellis,1984) points, do occur (Fig. 2). Although they date in the middle of YD time, the exact age of these developments in radiocarbonyears can be endlessly debated and it does not help that thereseems to be a radiocarbon plateau right in this same intervalaround 10,600 e 10,400  14 C BP (e.g., Fiedel, 1999:98 e 99) such thatmany actual years (800  þ  calendar years) are compressed intoa short interval of radiocarbon time. In any case, long acceptedrelative methods of archaeological dating, principally typologicaldating and a modi 󿬁 ed variant of contextual seriation, clearlysuggest the Clovis-like, Barnes and Crow 󿬁 eld forms representa time series (Ellis and Deller, 1997:7 e 8; contra Eren,2009:404 e 405). As all these  󿬂 uted point types occur above andlining the strandline of pro-glacial Lake Algonquin in the Huronbasin (see below), but not below it, this indicates they pre-date thedraining of that lake (Ellis and Deller,1986; Deller and Ellis,1988),which occurred around 10,400 e 10,300  14 C BP (Karrow et al.,1975). Following the  󿬂 uted point forms in the east are presumed un 󿬂 utedforms such as Holcombe (Fitting et al., 1966) and eventually Hi-Loand even some Agate Basin forms. Unlike the  󿬂 uted point forms,these types do occur below, as well above, the strandline of LakeAlgonquin age and therefore to some extent must post-date ca.10,400 e 10,300 14 C BP (e.g., Ellis and Deller,1986). Moreover, and incomplete agreement with this geochronological evidence, dates onpoints comparable to Holcombe forms from east of the Great Lakesclearly indicate a date in the 10,300 to 10,000  14 C BP time period(Bradley et al., 2008:150 e 151). In short, cross-dating, availablegeochronological evidence, relative  “ stylistic ”  dating techniquesand the few radiocarbon dates available are completely compli-mentary and provide a consistent temporal sequence for the majorcategories employed here.In summary, the YD as a climatic interval began after peoplemaking Clovis-like points had entered the area. The Clovis-likeperiod continued until at least the beginning of the YD andalthough there is some disagreement on this fact, probably lastedsome time into the early part of the YD. Subsequent developmentsacross the Great Lakes such as Folsom and Barnes/Crow 󿬁 eld/Hol-combe undoubtedly fell completely within the middle to late YDwhereas the end of the YD occurred during Agate Basin to Hi-Lotimes (Table 2). At the present time it is most plausible that theonset of any environmental changes would have affected humanpopulations and led to shifts evident in the archaeological recordbetween the earliest Clovis-like populations as a whole andsubsequent middle to late Paleoindian populations. Even if theClovis-likeperiodlastedintotheearlyYD,thisoutcomewouldhaveno effect on the arguments made here. As will become clear below,inthemainareasoffocustheinitiationoftheYDasaclimaticeventat 10,800  14 C BP does not seem to correspond with any immediatemajor changes in  “ on the ground ”  plant and animal communities/environments. Such a lag effect is not necessarily unexpected (seeMeltzerandHolliday,2010:2).Changesinthosebioticcommunitiesthat did lead to changes in the behavior of Great Lakes PaleoindianpeoplesmayhavebeeninitiatedbytheYD,butthoseeffectsdidnotappear until some time later and well into that climatic interval orcloser to Middle Paleoindian times. For example, paleoenvir-onmental specialists attribute a re-advance of the glacial ice sheetinto northern Wisconsin to the YD, but the actual re-advance didnot occur until after ca.10,500 BP or well into the YD  per se . 3. Analyses As noted, there are observable changes in the archaeologicalrecord of the Great Lakes area in late Pleistocene times, and thesechanges may be related  in part   to human responses to environ-mental shifts in 󿬂 uenced by the YD event. Eren (2009:400 e 407) inhis search for potential changes in the archaeological record of theeastern Great Lakes focused on  󿬁 ve characteristics including: thetype composition of stone tool assemblages/kits, site/assemblagesizes, the kinds of cultural features documented, distance to theprimary toolstone source employed, and the geographic distribu-tion of different components. The focus here is on only three linesofevidence,twoofwhichwerealsoaddressedbyEren(2009).Theyinclude:a)residentialmobilityscaleasmeasuredbydistancetothemost common stone source used at a site; b) changes in frequencyof sites/ 󿬁 nds over time; and c) changes in the overall distributionsof sites. These aspects were also chosen because it is believed that Fig. 2.  Chart Correlating Western and Eastern Great Lakes Point Types/CulturalComplexes and Younger Dryas Event.  Table 1 Frequency of Ontario Sites and Findspots by Point Type/Cultural Complex. a Point Type n %Clovis-like 55 43.7Barnes 38 30.2Crow 󿬁 eld 25 19.8Holcombe 8 6.4Total 126 100.1 a Chi-Square ¼ 37.746, df  ¼ 3,  p ¼ .000; basedondatafromHanson(2010)withadditions by Ellis.  Table 2 Frequency of Ontario Sites and Findspots by Point Type/Cultural ComplexCombining Crow 󿬁 eld and Holcombe. a Point Type n %Clovis-like 55 43.7Barnes 38 30.2Crow 󿬁 eld/Holcombe 33 26.2Total 126 100.1 a Chi-Square ¼ 6.333,  df  ¼ 2,  p ¼ .042. C.J. Ellis et al. / Quaternary International 242 (2011) 534 e 545 536  the evidence is quiterobust, unlike some of the evidence examinedby Eren (2009). For example, while the present authors havespeculated on changes in tool kit size and composition over time(e.g.,EllisandDeller,1997:11 e 16;Ellis,2004b),thetypologyofsuchassemblages is still poorly developed, the samples described indetail inadequate, and it is uncertain just what the commonlyrecognized tool types/classes, especially the broad classes like “ endscrapers ”  or  “ sidescrapers ”  employed by Eren (2009), actuallyrepresent in terms of speci 󿬁 c site activities. Such gross categoriescould mask a wide range of activity variability (see especially Ellis,1984, 1993; Ellis and Deller, 1988). Similarly, as most Paleoindiansitesareinplowed 󿬁 elds,andapparentlymostPaleoindianfeaturesin general are relatively shallow and ephemeral (e.g., Surovell andWaguespack, 2007), there are very few convincing Paleoindianfeatures of any kind that have been reported in detail. The knownsample is simply inadequate to evaluate change in this aspect.The Great Lakes is a vast area and there is variability betweeneast and west in terms of the cultural complexes and their repre-sentation and there are also environmental differences, so it isimpossible to discuss the archaeological record in a uniformmanner. Therefore, this presentation is organized in terms of theeast-west distinction beginning with the east. For the sake of brevity, and because the ability to amass substantial and debuggeddata sets is best for the areas in which the present authors havecarried out research, the data often are discussed as they pertainonly to certain areas within the east and west such as Ontario orWisconsin. However, there are less pragmatic reasons for discus-sing even smaller areas, as there are signi 󿬁 cant environmentaldifferences at even smaller scales such as northern Ohio versussouthernOntario.Aspeopleobviouslyadapttolocalconditions,theresponses can vary over these relatively small areas. If one was toexamine certain evidence for change at a larger scale, such as thewhole eastern Great Lakes, these spatially variable responses couldprovide a lot of noise and obscure local level responses. Sensitivityto regional (and temporal) variation rather than over-generalizingis badly needed in Paleoindian studies and has the potential toreveal a great deal of often overlooked subtlety in their adaptations(e.g., Wright, 1989; Ellis and Deller, 1997; Bamforth and Becker,2000:287 e 288).  3.1. Eastern Great Lakes The backdropof this story is the Great Lakes themselves. Duringthe period of concern here, coincident with the 󿬂 uted point relatedoccupations, most of the lake levels, excepting Ontario, were abovemodern levels and were fed by the retreating Laurentide ice sheet(hereafter LIS) ( Jackson et al., 2000; Kincare and Larson, 2009; seeFig. 3). Notable here, as it 󿬁 gures prominently in discussions below,is the pro-glacial Lake Algonquin (or perhaps immediately post-Algonquin Lake Ardtrea; see Jackson et al., 2000 for discussion)shoreline in the Michigan and Huron basins mentioned earlier(Fig.3a).Coincidentwiththeshift toun 󿬂 utedpoints,thelakelevelsdropped from Algonquin levels to below modern because the icesheet retreated to the north and exposed a lower outlet (Fig. 3b). Itis obvious that many Late Paleoindian sites are now under water asare many Early Paleoindian  󿬂 uted point locations in areas like theLake Ontario basin ( Jackson et al., 2000:432 e 433)Against this backdropthe biotic environment was also changingas shown in Fig. 4, which synthesizes the data from the NorthAmerican Pollen Data Base for Michigan and Ontario. As longrealized, the changes are generally successional, with spruce beingreplaced by pine and eventually pine being replaced by moretemperate deciduous species. In the process there was a shift frommore open parkland/woodland vegetation to more closed forest(e.g., McAndrews, 1994; Hupy and Yansa, 2009). This generallysuccessional process was well under way by the time peopleentered the area. For Michigan and Ontario, the compiled pollendata suggest there may have been a slight rebound of spruce andnon-arboreal pollen at the time of the initiation of the YD around10,800  14 C BP (Fig. 4a e b; see also Lewis and Anderson, 1992:244)but this event was minor and short-lived. The only de 󿬁 nitiveindicationofsigni 󿬁 cant,longertermchangeassociatedwiththeYDis in the southernpartof the area on the till plains of northern Ohioand Indiana (e.g., Shane, 1994) where pollen sites like Stotzel-Leis(see Fig. 1) demonstrate, when contrasted with Ontario-Michigan,the high degree of environmental spatial variability (Figs. 4 and 5).Analyses by Linda Shane (1987) show that by 11,000  14 C BP theStotzel-Leis locality was an open woodland with an abundance of deciduous species like oak, ash and ironwood and with spruce asa minor component  e  a vegetation cover much unlike anythingseentoday(Fig.5).However,between11,000and10,500 14 CBP,oakdeclines drastically and spruce increases rapidly, a trend Shane(1987:18) relates to the YD. Within a short period, however,sprucedeclinesandpinequicklyreplacesituntilafter10,500 14 CBPwhen deciduous species rebound.The decline of spruce and rapid rise of pine indicates the YDresulted in somewhat dry conditions (Shuman et al.,2002:1784 e 1787). In fact, across the area the replacement of spruce by pine may not be controlled primarily by temperature asboth species have similar tolerances but by moisture availability;pine is more drought resistant (Shuman et al., 2002:1787; Chinn et al., 2004). Such drying out is also evident to the north in Mich-iganandOntariowhereonesees,forexample,thatashpollendrops Fig. 3.  Maps of Eastern Great Lakes Showing Changing Lake levels and DrainagePatterns. Light gray areas indicate modern lake levels while dark gray areas show lakelevels of the late Pleistocene - early Holocene. Arrows show direction of Great LakesdrainageA:Extentof lakes at time of Lake Algonquin (pre-10,400 BP; Note: some arguelevels in the Lake Erie basin were below modern at this time; see Jackson et al., 2000for discussion); B: Lowered lake levels after 10,400 BP. C.J. Ellis et al. / Quaternary International 242 (2011) 534 e 545  537  signi 󿬁 cantly (Fig. 4c). This species is most likely black ash thatfavors poorly drained soil (Grimm and Jacobson, 2004). In sum, itseems there was both a major drying out in the area along with anincrease in forest closure at this time (Shuman et al., 2002). Thisevent would have made active glacial lake shorelines like Algon-quin, and recently drained lake shores and lake bottoms, moreattractive  –  these wetland "openings" would have been a highlyattractive environmental niche.To summarize (Fig. 6), there seems to have been a more openspruce-dominated vegetation during Clovis-like occupations priorto and even into the initial stages of the YD. This association isreinforced by information from archaeological sites such as therecovery of species characteristic of open areas like the Arctic Foxfrom the Udora site in Ontario (Storck and Spiess, 1994:132). Amore closed and drier pine dominated vegetation came to the foreduringtheMid-Paleo,anddeciduouselementsenteredaftertheYD(Fig. 6). As well, extensive drained lake beds were present after theYD in late Hi-Lo times. Vegetation succession probably would haveoccurred without the Younger Dryas and in fact, was well underway before it. What perhaps the YD did was direct that successionin certain ways such as providing the dry conditions favoring taxasuch as the pine spread in Ohio or perhaps because of coolingeffects, maintaining open areas to the north for longer periods inspruce-dominated vegetations. In fact, cooling may have main-tained certain environments such as open spruce parkland longeras a whole into the YD, especially in the more northern parts of thearea, and may actually have allowed the earliest peoples of theregion to maintain certain patterns of land use and resourceexploitationforlongerperiodsratherthantochange.Itisintriguingto think that the initiation of the YD may have led to no changes,the reverse of the normal thinking about its environmental effects.Itmustbeexplicitlystressedwhathasbeenimplicit,thatthenatureof thesechanges wastime-transgressivefromsouthtonorthacrossthe area. For example, Fig. 7 shows plotted isopolls of criticalpercentages of certain pollen types for southern Ontario compiledbyMuller(1999)thatshowmoreopenareasandsprucedominancelasted longer during the YD to the north-northeast in that area.Turning to the archaeological record, and its ties or lack thereof to the YD, there are clear changes over time. One of the mostobvious is in distance to lithic source data. Fig. 8 plots distance tothe main source represented at each site. On average Clovis e likesites are 50 km farther from sources than the subsequent MiddlePaleoindian ones (171.15 versus 123.90 km). There are also noMiddle Paleo sites over 200 km from the source while there areseveral Clovis-like ones at up to 550 km or more away. The averagedistance itself is not signi 󿬁 cant if one uses a  t  -test [ t   (unequalvariances) ¼ 1.549,  df  ¼ 31.501;  p ¼ .131] but thatis misleading;thesample of Middle Paleoindian sites is biased toward ones fartherfrom the source (e.g.,150 e 200 km) because of a number of Barnessites in the same area on the same raw material in southwestern Fig. 5.  Changing Pollen Frequencies at the Stotzel-Leis site, Ohio based on datacontributed by Linda Shane to the on-line North American Pollen Data Base. Pollencounts from one anomalous level in the pollen core are omitted for clarity of presentation. Fig. 6.  Correlation of Environmental Changes and Cultural Complexes in Eastern GreatLakes Area. Fig. 4.  Changing Pollen Frequencies in Michigan-Ontario during the time of theYounger Dryas. Based on compiled data from on-line North American Pollen Data Base. C.J. Ellis et al. / Quaternary International 242 (2011) 534 e 545 538
Search
Similar documents
View more...
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x