Phytoliths and Pollen, the Microscopic Plant Remains in Pliocene Volcanic Sediments Around Laetoli, Tanzania

  • Lloyd RossouwEmail author
  • Louis Scott
Part of the Vertebrate Paleobiology and Paleoanthropology Series book series (VERT)


We analyzed sediment samples collected from several localities at different stratigraphic levels at Laetoli (i.e., Lower Laetolil Beds [LLB], Upper Laetolil Beds [ULB] and the overlying Upper Ndolanya Beds [UNB]) to establish a record of vegetation succession spanning intermittent periods between 4.3 and 2.66 Ma during the Pliocene. No reliable pollen spectra were found, but phytoliths, especially those of grasses (Poaceae), were investigated. A considerable time interval of deposition for the sequence, combined with a relatively low sample yield, allowed us to present only a low-resolution sequence of environmental changes, but one with marked grass cover variation. Grass was a ubiquitous, but never a dominant vegetation component in the LLB, ULB and the UNB sequences, with a general succession from mainly C3 grass types in the LLB and older ULB levels to more C4 grass types in the younger ULB and UNB. The record lends support to fossil herbivore analyses and δ13C isotope studies, which suggest more heterogeneous habitats and a combination of C3/C4 grassland conditions in the ULB and UNB sequences (Andrews 1989; Kingston and Harrison 2007; Kovarovic and Andrews 2007). Productive samples suggest wet, C3 conditions in the LLB and potentially dry, C3 conditions in the lower part of the ULB. A shift from drier to more mesic C4 grass conditions is recorded in the upper part of the ULB. Arid C4 grassland environments occurred during UNB deposition.


Grass silica Palynology Pollen preservation Past environment Vegetation change 



We thank Terry Harrison for the invitation to take part in the Laetoli project. LS collected most of the pollen samples during the 2000 field season with the help of team members especially John Kingston, while Terry Harrison and LR collected more during following seasons. LR collected the phytolith samples during the 2004 field season with the help of team member John Kingston. Charles Peters kindly provided unpublished data about his research on termitaria and phytolith preservation in East Africa. Petrus Chakane processed the samples chemically in the palynology laboratory at the UFS. The National Research Foundation (NRF) supported laboratory work (Gun 2053236). Any opinions, findings, and conclusions are those of the authors and the NRF does not accept any liability in regard thereto. Travel funds and field support were provided by an NSF grant (BCS-0309513) to Terry Harrison.


  1. Albert, R. M., & Weiner, S. (2001). Study of phytoliths in prehistoric ash layers using a quantitative approach. In J. D. Meunier & F. Coline (Eds.), Phytoliths: Applications in earth sciences and human history (pp. 251–266). Lisse: Balkema.Google Scholar
  2. Alexandre, A., Meunier, J. D., Lezine, A. M., Vincens, A., & Schwarz, D. (1997). Phytoliths: Indicators of grassland dynamics during the late Holocene in intertropical Africa. Palaeogeography, Palaeoclima­tology, Palaeoecology, 136, 213–229.CrossRefGoogle Scholar
  3. Andrews, P. J. (1989). Palaeoecology of Laetoli. Journal of Human Evolution, 18, 173–181.CrossRefGoogle Scholar
  4. Andrews, P. J., & Bamford, M. (2008). Past and present vegetation ecology of Laetoli, Tanzania. Journal of Human Evolution, 54, 78–98.CrossRefGoogle Scholar
  5. Barboni, D., Bonnefille, R., Alexandre, A., & Meunier, J. D. (1999). Phytoliths as palaeoenvironmental indicators, West Side Middle Awash Valley, Ethiopia. Palaeogeography, Palaeoclimatology, Palaeoecology, 152, 87–100.CrossRefGoogle Scholar
  6. Barboni, D., Bremond, L., & Bonnefille, R. (2007). Comparative study of modern phytolith assemblages from inter-tropical Africa. Palaeogeography, Palaeoclimatology, Palaeoecology, 246, 454–470.CrossRefGoogle Scholar
  7. Bonnefille, R. (1977). Palynological research at Olduvai Gorge. National Geographic Society, 1976 Projects, 227–243Google Scholar
  8. Bonnefille, R., & Riollet, G. (1987). Palynological spectra from the Upper Laetolil Beds. In M. D. Leakey & J. M. Harris (Eds.), Laetoli: A Pliocene site in northern Tanzania (pp. 52–61). Oxford: Clarendon.Google Scholar
  9. Bonnefille, R., & Vincens, A. (1985). Apport de la palynologie à l’environnement des hominidés d’Afrique orientale. In M. Beden, A. K. Behrensmeyer, N. T. Boaz, R. Bonnefille, C. K. Brain, H. B. S. Cooke, Y. Coppens, R. Dechamps, V. Eisenmann, A. Gentry, D. Geraads, R. Geze, C. Guerin, J. Harris, J.-C. Koeniguer, R. Letouzey, G. Petter, A. Vincens, & E. Vrba (Eds.), L’environnement des hominidés au Plio-Pléistocène (pp. 237–278). Paris: Masson.Google Scholar
  10. Bonnefille, R., Potts, R., Chalié, F., Jolly, D., & Peyron, O. (2004). High-resolution vegetation and climate change associated with Pliocene Australopithecus afarensis. Proceedings of the National Academy of Sciences, 101, 12125–12129.CrossRefGoogle Scholar
  11. Bremond, L., Alexandre, A., Hely, C., & Guiot, J. (2005). A phytolith index as a proxy of tree cover density in tropical areas: Calibration with Leaf Area Index along a forest-savanna transect in southeastern Cameroon. Global and Planetary Change, 45, 277–293.CrossRefGoogle Scholar
  12. Brown, D. A. (1984). Prospects and limits of a phytolith key for grasses in the central United States. Journal of Archaeological Science, 11, 345–368.CrossRefGoogle Scholar
  13. Brune, K., & Kuhl, M. (1996). pH profiles of the extremely alkaline hindguts of soil-feeding termites (Isoptera: Termitidae) determined with microelectrodes. Journal of Insect Physiology, 42, 1121–1127.CrossRefGoogle Scholar
  14. Carrión, J. S., & Scott, L. (1999). The challenge of pollen analysis in palaeoenvironmental studies of hominid beds: The record from Sterkfontein caves. Journal of Human Evolution, 36, 401–408.CrossRefGoogle Scholar
  15. Coetzee, J. A. (1964). Evidence for a considerable depression of the vegetation belts during the Upper Pleistocene on the East African mountains. Nature, 204, 564–566.CrossRefGoogle Scholar
  16. Danin, A. (1990). Deterioration of limestone walls in Jerusalem and marble monuments in Rome caused by cyanobacteria and cyanophilous lichens. International Biodeterioration, 26, 397–417.CrossRefGoogle Scholar
  17. Deino, A. (2011). 40Ar/39Ar dating of Laetoli, Tanzania. In: Harrison, T. (Ed.), Paleontology and geology of Laetoli: Human evolution in context (Geology, geochronology, paleoecology and paleoenvironment, vol. 1, pp. 77–97). Dordrecht: Springer.Google Scholar
  18. DeMenocal, P. B. (1995). Plio-Pleistocene African climate. Science, 270, 53–59.CrossRefGoogle Scholar
  19. DeMenocal, P. B. (2004). African climate change and faunal evolution during the Pliocene-Pleistocene. Earth and Planetary Science Letters, 220, 3–24.CrossRefGoogle Scholar
  20. Ditchfield, P., & Harrison, T. (2011). Sedimentology, litho-stratigraphy and depositional history of the Laetoli area. In T. Harrison (Ed.), Paleontology and geology of Laetoli: Human evolution in context (Geology, geochronology, paleoecology, and paleoenvironment, vol. 1, pp. 47–76). Dordrecht: Springer.Google Scholar
  21. Drake, R., & Curtis, G. (1987). K-Ar geochronology of the Laetoli fossil localities. In M. D. Leakey & J. M. Harris (Eds.), Laetoli: A Pliocene site in northern Tanzania (pp. 48–51). Oxford: Clarendon.Google Scholar
  22. Ehleringer, J. R., Sage, R. F., Flanagan, L. B., & Pearcy, R. W. (1991). Climate change and the evolution of C4 photosynthesis. Trends in Ecology & Evolution, 6, 95–99.CrossRefGoogle Scholar
  23. Ehleringer, J. R., Cerling, T. E., & Helliker, B. R. (1997). C4 photosynthesis, atmospheric CO2 and climate. Oecologia, 112, 285–299.CrossRefGoogle Scholar
  24. Ellis, R. P. (1977). Distribution of the Kranz syndrome in the southern African Eragrostideae and Panicoideae. Agroplantae, 9, 73–110.Google Scholar
  25. Ellis, R. P., Vogel, J. C., & Fuls, A. (1980). Photosynthetic pathways and the geographical distribution of grasses in southwest Africa Namibia. South African Journal of Science, 76, 307–314.Google Scholar
  26. Erdtman, G. (1960). The acetolysis method. A revised description. Svensk Botanisk Tidskrift, 54, 561–564.Google Scholar
  27. Fredlund, G. G., & Tieszen, L. L. (1994). Modern phytolith assemblages from the North American great plains. Journal of Biogeography, 21, 321–335.CrossRefGoogle Scholar
  28. Gibbs Russell, G. E. (1985). PRECIS: The National Herbarium’s computerized information system. South African Journal of Science, 81, 62–65.Google Scholar
  29. Gibbs Russell, G. E. (1988). Distribution of subfamilies and tribes of Poaceae in Southern Africa. Monographs in Systematic Botany, Missouri Botanical Gardens, 25, 555–566.Google Scholar
  30. Grab, S., Scott, L., Rossouw, L., & Meyer, S. (2005). Holocene palaeo‑environments inferred from a sedimentary sequence in the Tsoaing River Basin, western Lesotho. Catena, 61, 49–62.CrossRefGoogle Scholar
  31. Harrison, T., & Kweka, A. (2011). Paleontological localities on the Eyasi Plateau, including Laetoli. In T. Harrison (Ed.), Paleontology and geology of Laetoli: Human evolution in context (Geology, geochronology, paleoecology and paleoenvironment, vol. 1, pp. 17–45). Dordrecht: Springer.Google Scholar
  32. Hattersley, P. W. (1983). The distribution of C3 and C4 grasses in Australia in relation to climate. Oecologia, 57, 113–128.CrossRefGoogle Scholar
  33. Hay, R. L. (1987). Geology of the Laetoli area. In M. D. Leakey & J. M. Harris (Eds.), Laetoli: A Pliocene site in northern Tanzania (pp. 23–47). Oxford: Clarendon.Google Scholar
  34. Henderson, Z. L., Scott, L., Rossouw, L., & Jacobs, Z. (2006). The dating, palaeoenvironments and archaeology of the Sunnyside 1 site, Clarens, South Africa. Archaeological Papers of the American Anthropological Association, 16, 139–149.CrossRefGoogle Scholar
  35. Horrocks, M. (2005). A combined procedure for recovering phytoliths and starch residues from soils, sedimentary deposits and similar materials. Journal of Archaeological Science, 32, 1169–1175.CrossRefGoogle Scholar
  36. Kingston, J. D., & Harrison, T. (2007). Isotopic dietary reconstructions of Pliocene herbivores at Laetoli: Implications for early hominin paleoecology. Palaeogeography, Palaeoclimatology, Palaeoecology, 243, 272–306.CrossRefGoogle Scholar
  37. Klein, R. G. (1999). The human career. Chicago: The University of Chicago Press.Google Scholar
  38. Kovarovic, K., & Andrews, P. (2007). Bovid postcranial ecomorphological survey of the Laetoli paleoenvironment. Journal of Human Evolution, 52, 663–680.CrossRefGoogle Scholar
  39. Lentfer, C. J., & Boyd, W. E. (1998). A comparison of three methods for the extraction of phytoliths from sediments. Journal of Archaeological Science, 25, 1152–1183.CrossRefGoogle Scholar
  40. Lentfer, C. J., & Boyd, W. E. (1999). An assessment of techniques for the deflocculation and removal of clays from sediments used in phytolith analysis. Journal of Archaeological Science, 26, 31–44.CrossRefGoogle Scholar
  41. Livingstone, D. A., & Clayton, W. D. (1980). An altitudinal cline in tropical Africa grass floras and its palaeoecological significance. Quaternary Research, 13, 392–402.CrossRefGoogle Scholar
  42. Madella, M., Alexandre, A., & Ball, T. (2005). International Code for Phytolith Nomenclature. Annals of Botany, 96, 253–260.CrossRefGoogle Scholar
  43. McLean, B., & Scott, L. (1999). Phytoliths in sediments of the Pretoria Saltpan and their potential as indicators of environmental history at the site. In T. C. Partridge (Ed.), Tswaing-investigations into the origin, age and palaeoenvironments of the Pretoria Saltpan (pp. 167–171). Pretoria: Council for Geosciences.Google Scholar
  44. Mulholland, S. C. (1989). Phytolith shape frequencies in North Dakota grasses: A comparison to general patterns. Journal of Archaeological Science, 16, 489–511.CrossRefGoogle Scholar
  45. Mulholland, S. C., & Rapp, G. J. (1992). A morphological classification of grass silica-bodies. In G. J. Rapp & S. C. Mulholland (Eds.), Phytolith systematics. Emerging issues. Advances in archeological and museum science 1 (pp. 65–81). New York: Plenum.Google Scholar
  46. Piperno, D. R. (1988). Phytolith analysis: An archeological and geological perspective. London: Academic.Google Scholar
  47. Rovner, I. (1971). Potential of opal phytoliths for use in palaoecological reconstruction. Quaternary Research, 1, 343–359.CrossRefGoogle Scholar
  48. Sage, R. F. (2004). The evolution of C4 photosynthesis. The New Phytologist, 161, 341–370.CrossRefGoogle Scholar
  49. Scott, L. (1995). Pollen evidence for vegetational and climate change during the Neogene and Quaternary in Southern Africa. In E. Vrba, G. Denton, T. C. Partridge, & L. H. Burckle (Eds.), Paleoclimate and evolution with emphasis on human origins (pp. 65–76). New Haven: Yale University Press.Google Scholar
  50. Scott, L. (2002). Grassland development under glacial and interglacial conditions in Southern Africa: Review of pollen, phytolith and isotope evidence. Palaeogeography, Palaeoclimatology, Palaeoecology, 177, 47–57.CrossRefGoogle Scholar
  51. Scott, L., & Bonnefille, R. (1986). A search for pollen from the hominid deposits of Kromdraai, Sterkfontein and Swartkrans: Some problems and preliminary results. South African Journal of Science, 82, 380–382.Google Scholar
  52. Scott, L., & Rossouw, L. (2005). Reassessment of botanical evidence for palaeoenvironments at Florisbad, South Africa. South African Archeological Bulletin, 60, 96–102.Google Scholar
  53. Scott, L., Fernandez-Jalvo, Y., Carrión, J. S., & Brink, J. S. (2003). Preservation and interpretation of pollen in hyena corprolites: Taphonomical observations from Spain and Southern Africa. Palaeontologia Africana, 39, 83–91.Google Scholar
  54. Ségalen, L., Lee-Thorp, J. A., & Cerling, T. (2007). Timing of C4 grass expansion across sub-Saharan Africa. Journal of Human Evolution, 53, 549–559.CrossRefGoogle Scholar
  55. Stromberg, C. A. E. (2002). The origin and spread of grassland-dominated ecosystems in the late Tertiary of North America: Preliminary results concerning the evolution of hypsodonty. Palaeogeography, Palaeoclimatology, Palaeoecology, 177, 59–76.CrossRefGoogle Scholar
  56. Stromberg, C. A. E. (2004). Using phytolith assemblages to reconstruct the origin and spread of grass-dominated habitats in the great plains of North America during the late Eocene to early Miocene. Palaeogeography, Palaeoclimatology, Palaeoecology, 207, 239–275.CrossRefGoogle Scholar
  57. Tieszen, L., Senyimba, M. M., Imbamba, S. K., & Troughton, J. H. (1979). The distribution of C3 and C4 grasses and carbon isotope discrimination along an altitudinal and moisture gradient in Kenya. Oecologia, 37, 337–350.CrossRefGoogle Scholar
  58. Twiss, P. C., Suess, E., & Smith, R. M. (1969). Morphological classification of grass phytoliths. Proceedings of the Soil Science Society of America, 33, 109–115.CrossRefGoogle Scholar
  59. Vogel, J. C., Fuls, A., & Ellis, R. P. (1978). The geographical distribution of Krantz grasses in South Africa. South African Journal of Science, 74, 209–215.Google Scholar
  60. Wooller, M. J., Street-Perrott, F. A., & Agnew, A. D. Q. (2000). Late Quaternary fires and grassland plaeoecology from charred grass cuticles in Lake sediments. Palaeogeography, Palaeoclimatology, Palaeoecology, 164, 207–230.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Department of ArchaeologyNational MuseumBloemfonteinSouth Africa
  2. 2.Department of Plant SciencesUniversity of the Free StateBloemfonteinSouth Africa

Personalised recommendations