OFR 151.pdf - CRC LEME

2. Analysis of a Plio-Pleistocene lacustrine sequence preserved in the Stony Creek
Basin, Daylesford in central Victoria. This site demonstrates that a number of
biostratigraphically important taxa survived on the Central Highlands of Victoria some 2-5
million years after they became extinct at low elevations in the Gippsland and Murray Basins
(cf. Macphail 1997, Partridge 1999, Sniderman et al. 2003, 2007, Macphail 2006a).
Examples are (NLR in parentheses) a fern Cyatheacidites annulatus (Lophosoria) and a shrub
gymnosperm Podosporites microsaccatus (cf Microcachrys). The finding highlights the need
to find other palynostratigraphic criteria to subdivide Plio-Pleistocene time, e.g. by a detailed
analysis of the Calival and Shepparton Formations.
3. Analysis of Early Eocene sequences at Regatta Point and Lowana Road at Strahan on
the West Coast of Tasmania. Macrofossils and microfossils preserved in these outcrops
provide not only an exceptional record of the vegetation growing at high palaeolatitudes in
southern Australia during this critical warm period but (Lowana Road) also preserve what
may be the earliest known organic fossils of Eucalyptus (R. Carpenter, R.S. Hill and G.
Jordan unpubl. results). It is possible that deeper intervals within the section preserve macro-
and microfossils accumulating during the PETM Event itself. Carpenter et al. (2004) have
described a broadly contemporary Early Eocene flora from near the summit (1723 m asl) of
Mt. Hotham in eastern Victoria.
4. A review of palaeobotanical evidence for the onset of climate-forced xeromorphy
(Hill and Brodribb 2001). This study provides compelling evidence of the adaptive responses
to aridification in two prominent and widespread Australian sclerophyll plant families during
the Late Tertiary.
Regional comparisons
A highly useful review of the composition and ecology of modern tropical and paratropical
rainforests, their origins in the Cretaceous and their evolution during the Cenozoic has been
published by Morley (2000). This compares the Australian palaeobotanic record with those
of South-East Asia and more distant landmasses, viz. Africa, India, New Zealand, South
America, North America and Europe, and uses palynostratigraphic evidence to identify plant
dispersal paths between these landmasses during the Tertiary.
How enduring the palaeoclimatic reconstructions inferred herein for the various regions of
Australia, or indeed for any of the above continental landmasses, will be is unclear. Very
recent discoveries such as the presence of glaciers in Greenland some 20 million years earlier
than previously documented (Eldrett et al. 2007) suggests a short 'shelf life'.
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