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Resumo Estuda-se a carga transportada nas patas por 267 abelhas de Melipona seminigra durante um ano, em Manaus. Dessas, 104 (39%) não transportavam pólen, mas sim látex (no nosso caso do fruto de Vismia, inclusive com sementes), resinas e barro. Das 163 restantes (61%), 99 transportavam pólen de uma só espécie, 38 (23%) transportavam de duas espécies e 26 (16%) de três ou mais. As abelhas colheram pólen de 19 famílias e 25 gêneros diferentes. Apenas 13 tipos de pólen foram identificados até o nível de espécie.

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ABSTRACf Sludics done in BraziJ, under lhe CNPq (Brazil) and ORSTOM (France) agreerncnl. • lIowt:d us 10 envisage lhe general IICnd of climatic ehangcs lhal oocurred during lhe lasl 60.000 years AI fiM. examinalion of successi\'c aocumulalion and ewsion phases, rec(lrded wíthin Cenual 8razilian valley dcposics, provided evidence of important changc::s in s10pc vegetalion etwer and in lhe bydrauJie regime of water coursc::s. and IM:nce charactcristics of precipitalion and elimate regimes. Sludks of Tamanduii river valley deposilS in lhe town of São SimAo (State of SJo Paulo) I.howcd lhal belween 32 and 21 ky. B.P. the elimale was bumid. whercas belwoen 11 and 11 ky. B.P. il was dJy wilb vel")' scaroc anel SlrOng nLins. From 10 ky lo 8.~ ky. B.P. tbe climale was humid 100. Finally, afier 7 .~ ky. B.P. lhe dcpoIIils revcalcd lhe existenceofseveraldJyepii0de5withlnagloba.llyhumidclimate Palyno1ogicat and scdimentological anaI)'SC5 of Iacu5trine deposilS sampled b)" vibrocorers in lhe Eastem ADIazon (Catajú, Stale of Pará) and in Central Brazil (SalitIe, State of MiIW Gerais) pennittcd us looullinc IheevolutionaJy historyoflhevegetation caver wilhin tbcsc regiDos duriq lhe last 60,000 years for CatajAs and 30,000 years for SalilIC and Ibus 10 have a prelúrúnary idca IIbouI theif past elimales. Tbcn, il was possibJc lo show lhal at CaraJAs regression ofthe evergreeII rainforest occurrcd f OU! times. aI aboul 60. 40. betwoen 23-11 and 7-4 lcy. e.p. Moreover, apparenlly lhe lasl rainforest regrel5ion episode WdS quite diffcrenl rromthepreviousthreccpisodes.AISalitre,themost cbaractcrislieistheindicationofthe cxistenceofAraucaria (oral betwocD 12 and 8 .~ 'lcy. B.P. This Arallcaria fOre$l location is cJearly much funber north than aI pre:seDt. which $IIggesU; that during lhal time lhe: elimale W8$ wcttu and colder. Finally, studies devcloped a10ng tbecentral Brazilian eoast a1lowcd us 10 soow cvidcnce of wind-ldriven cllange in littoral dynamics during lhe: 1ast 5 ky. A detaikd ClWIlination of Doce river (Stale of l~. PakoonIoIopro.EonIipaflA, _ _ .~~.s.o~ ...

Abstract. This article presents the scientific rationale for an ambitious ICDP drilling project to continuously sample Late Cretaceous to modern sediment in four different sedimentary basins that transect the equatorial Amazon of Brazil, from the Andean foreland to the Atlantic Ocean. The goals of this project are to document the evolution of plant biodiversity in the Amazon forests and to relate biotic diversification to changes in the physical environment, including climate, tectonism, and the surface landscape. These goals require long sedimentary records from each of the major sedimentary basins across the heart of the Brazilian Amazon, which can only be obtained by drilling because of the scarcity of Cenozoic outcrops. The proposed drilling will provide the first long, nearly continuous regional records of the Cenozoic history of the forests, their plant diversity, andPublished by Copernicus Publications on behalf of the IODP and the ICDP. the associated changes in climate and environment. It also will address fundamental questions about landscape evolution, including the history of Andean uplift and erosion as recorded in Andean foreland basins and the development of west-to-east hydrologic continuity between the Andes, the Amazon lowlands, and the equatorial Atlantic. Because many modern rivers of the Amazon basin flow along the major axes of the old sedimentary basins, we plan to locate drill sites on the margin of large rivers and to access the targeted drill sites by navigation along these rivers.

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