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f iMethods for reconstructing past vegetation
based on macroplant fossils
Marion K BamfordBPI Palaeontology
University of the Witwatersrand
Johannesburg, South Africa
Botanical evidence 3 Ma to PresentBotanical evidence 3 Ma to PresentBotanical evidence 3 Ma to PresentBotanical evidence 3 Ma to Present
South AfricaSouth AfricaSterkfontein ~ 2.8 MaSterkfontein ~ 2.8 Ma
East AfricaEast AfricaKoobi Fora Koobi Fora –– Upper Upper
TaungTaungWonderwerk 2 Ma toWonderwerk 2 Ma to
ppppBurgi Mbr ~ 2 MaBurgi Mbr ~ 2 MaOmo River ShunguraOmo River ShunguraWonderwerk 2 Ma to Wonderwerk 2 Ma to
presentpresentSib dSib d 60 k60 k
Omo River Shungura Omo River Shungura Fm ~ 2 MaFm ~ 2 MaOlduvai 1 8 MaOlduvai 1 8 MaSibudu ~ 75Sibudu ~ 75--60 ka60 ka Olduvai ~ 1.8 MaOlduvai ~ 1.8 MaKoobi Fora Koobi Fora –– Okote Okote Mb 1 5 MMb 1 5 MMbr ~ 1,5 MaMbr ~ 1,5 Ma
Sources of dataSources of dataSources of dataSources of data
PollenPollenRegional, family/genus level, grassesRegional, family/genus level, grassesg , y g , gg , y g , g
PhytolithsPhytolithsL l? C3 C4 di l dL l? C3 C4 di l dLocal? C3 vs C4 grasses; dicots; palms; sedgesLocal? C3 vs C4 grasses; dicots; palms; sedges
MacroplantsMacroplantsppLocal; Rare, genus/species level; external Local; Rare, genus/species level; external morphology; vegetation structuremorphology; vegetation structuremorphology; vegetation structuremorphology; vegetation structure
Phytolith taphonomyPhytolith taphonomyPhytolith taphonomyPhytolith taphonomyS lS lSamplesSamples
Living plants (grasses, sedges, herbs, shrubs, trees)Living plants (grasses, sedges, herbs, shrubs, trees)Soil below living plantsSoil below living plantsSoil below living plantsSoil below living plantsFossil/archaeological sedimentsFossil/archaeological sediments
TaphonomyTaphonomyap o o yap o o yResultsResults
Reduction: plant Reduction: plant soil soil fossil sedimentfossil sedimentppMorphotypes lost: sedges, monocotsMorphotypes lost: sedges, monocotsAlkalinity, ground water, carbonate nodulesAlkalinity, ground water, carbonate nodules
Case study Case study –– Olduvai GorgeOlduvai Gorge
Olduvai GorgeOlduvai GorgeOlduvai GorgeOlduvai Gorge
Geotrenching in selected locations
Grassland below Grassland below T ff IFT ff IFTuff IFTuff IF
PollenPollenPollenPollenlumc nl/1070/patientenzorg/Pollen%20Informatie%20Dienst/Images/poaceae jpgjp
g
lumc.nl/1070/patientenzorg/Pollen%20Informatie%20Dienst/Images/poaceae.jpg
es/P
oace
aeg
rain
.jp
hoto
guid
eim
age
ges/
Phot
ogui
des
/prm
s/Se
dim
entp
ag
%20
and
%20
Land
frM
ars
h/RM
%20
Sed
s%
Poaceae
Olduvai Gorge LMB IIOlduvai Gorge LMB IIGuibourtia coleospermaGuibourtia coleospermapp
Phytoliths identified in T-107 2identified in T-107.2
Phytoliths identified in Spray paint layerSpray paint layer
Phytoliths identified in VEKsectionsection
RhizolithsRhizoliths
Fossil root profilesFossil root profilesFossil root profilesFossil root profiles
Modern analoguesModern analoguesModern analoguesModern analogues
l i li il d hl i li il d hSelection: climate, soil and topographySelection: climate, soil and topographyGeographically as close as possibleGeographically as close as possibleg p y pg p y pUndisturbed habitatUndisturbed habitatLong term easy accessLong term easy accessLong term easy accessLong term easy accessTaphonomyTaphonomyEg: Ngorongoro, Serengeti, Ol’Balbal Eg: Ngorongoro, Serengeti, Ol’Balbal depression; Lakes Manyara, Masek, Ndutu, depression; Lakes Manyara, Masek, Ndutu, p ; y , , ,p ; y , , ,Natron; Okavango Delta, Seekoeivlei NRNatron; Okavango Delta, Seekoeivlei NR
Ngorongoro CraterNgorongoro CraterNgorongoro CraterNgorongoro Crater
SerengetiSerengetigg
Open woodlandsp
Riverine woodlands
Open grasslandsp g
Kopjies
Lake ManyaraLake Manyara
Okavango DeltaOkavango Deltagg
Seekoeivlei Nature ReserveSeekoeivlei Nature ReserveSeekoeivlei Nature Reserve Seekoeivlei Nature Reserve
High altitude
Fresh water
Mixed grasses and sedges
Large mammals
ModernModernrootsroots
Termite tunnels, invertebrates or roots?
Termitaria, Termitaria, roots, roots,
rhizomesrhizomesrhizomesrhizomes
Criteria for identificationCriteria for identificationCriteria for identificationCriteria for identification
Root tracesRoot tracesMainly verticalMainly vertical
Termites or Termites or invertebratesinvertebratesyy
Branch downwardsBranch downwardsHierarchy of diametersHierarchy of diameters
Few size classesFew size classesBranch randomlyBranch randomlyHierarchy of diametersHierarchy of diameters
Rhizomes and rootsRhizomes and rootsBranch randomlyBranch randomly+/+/-- nodesnodes
Density decreases Density decreases verticallyvertically
Several generationsSeveral generations
Vegetation reconstructionVegetation reconstructionVegetation reconstructionVegetation reconstructionPeninsulaChannel Wetland
interiorWetlandedge
Monocots (few)Monocots dicots GrassesGrassesMonocots (few)Monocots,dicots Grasses, monocots, dicots, ferns
Grasses, sedges, dicots
fernsRootsSedges TyphaWoody
branches
Silicified woodsSilicified woodsSilicified woodsSilicified woods
NLRNLRNeed species Need species
PhysiognomyPhysiognomyVulnerability index V = Vulnerability index V = pp
determinationdeterminationLarge sampleLarge sample
yyV#/ VdiamV#/ VdiamTaxon independentTaxon independentLarge sampleLarge sample
Good modern databaseGood modern databaseTaxon independentTaxon independentNo African modern No African modern databasedatabasedatabasedatabase
Leaf impression fossilsLeaf impression fossilsLeaf impression fossilsLeaf impression fossils
NLRNLRNeed modern analogue Need modern analogue
PhysiognomyPhysiognomyCLAMP and othersCLAMP and othersgg
databasedatabase33°° and 4and 4°° venationvenation
Need East African Need East African modern databasemodern database33 and 4and 4 venationvenation
Some species not Some species not distinctdistinct
modern databasemodern databaseSouth African modern South African modern database starteddatabase starteddistinctdistinct database starteddatabase startedLarge sample neededLarge sample neededTaxon independentTaxon independent
Way forwardWay forward fossil macroplantfossil macroplantWay forward Way forward –– fossil macroplantfossil macroplant
Make databases for modern wood Make databases for modern wood physiognomyphysiognomyp y g yp y g yMake database for modern leaf features Make database for modern leaf features ––CLAMP etcCLAMP etcCLAMP, etc.CLAMP, etc.Make collections of comparative leavesMake collections of comparative leavesModern seed collectionsModern seed collectionsM d h l ll tiM d h l ll tiModern charcoal collectionsModern charcoal collections
Way forwardWay forwardWay forwardWay forward
Palynology and phytolith studies Palynology and phytolith studies -- modern and fossilmodern and fossilFind suitable wetlands to coreFind suitable wetlands to coreAltitudinal and latitudinal sequencesAltitudinal and latitudinal sequencesCompile existing databasesCompile existing databasesCompile existing databasesCompile existing databases
Check datingCheck datingCheck identificationsCheck identificationsCheck identificationsCheck identifications
Add new dataAdd new dataCorrelate East and South Africa Correlate East and South Africa –– probably not probably not synchronous climatessynchronous climates
Thank youThank youROCEEH, Senckenberg
MuseumMuseum
Heidelberg Academy of Science
NSF, Leakey Foundation. Wenner-Gren
PAST
Ngorongoro Crater - grassland
Ngorongoro Crater: Ngoitokitok forest-marsh transition
Lake Manyara: saline-alkaline lake, groundwater forest