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Abstract

Fossil woods have been recovered from Noiti to the south of the main Laetoli area and are of Lower Laetolil Bed age. Preservation is generally poor because of recrystalization but a variety of taxa have been tentatively identified. Where there is some uncertainty about the identification several possibilities have been given. The fossil woods are from the families Araliaceae, Buddlejiaceae, Caesalpinoideae, Celastraceae, Combretaceae, Dichapetalaceae, Euphorbi­aceae, Flacourtiaceae, Meliaceae, Mimosoideae, Myrtaceae, Ochnaceae, Rhamnaceae, Rubiaceae, Rutaceae and Verben­aceae. The flora represents woods from high to low altitudes that grew on the slopes of the volcano and were preserved in a lahar. A variety of soils and vegetation associations are implied from forest, evergreen woodland, dry woodland, bushland, riverine and wooded grassland, in a megathermal environment. Both taxonomic affinities and the vulnerability indices (non-taxonomic) of the woods are used to infer the paleoenvironment.

Keywords

Silicified wood vegetation associations montane woodland 

Notes

Acknowledgements

I am grateful to Louis Scott and Terry Harrison for the invitation to take part in the Laetoli expeditions, and to all the team members who helped collect fossil woods. Mr. D. Mbense is thanked for making the thin sections. The Tanzanian Commission for Science and Technology (COSTECH), the Tanzanian Department of Antiquities and the Ngorongoro Conservation Area Authority are also thanked for providing permits to carry out the research. This work was supported by NSF grants BCS-9903434 and BCS-0309513 (to Terry Harrison) and a PAST (Palaeontological Scientific Trust, South Africa) grant (to MKB).

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Bernard Price Institute for Palaeontological Research, School of GeosciencesUniversity of the WitwatersrandJohannesburgSouth Africa

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