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Glossifungites-demarcated discontinuities have been demonstrated to have stratigraphic significance. Unfortunately, their stratigraphic utility commonly eclipses the palaeoecological information derived from such surfaces. This paper attempts to identify factors that influence the nature of trace assemblages observed in modern firmgrounds. In particular, it focuses on the causes of lateral variability and erosional topography inherent to Glossifungitessurfaces. The extensive Pleistocene database at Willapa Bay is used to test the interpretations.

Fossil echinoderms are an important faunal component in Cenozoic rocks of Florida and the southeastern Coastal Plain of the USA, that provide useful information regarding diversity patterns and paleoecology for the formations in which they were deposited. The research presented in this paper significantly improves what is known about the stratigraphic distribution and diversity patterns of echinoids, comatulid crinoids, asteroids, and ophiuroids from the Middle Eocene through Pleistocene strata of Florida. Biostratigraphic distribution of echinoderms, specifically the echinoids, has not been synthesized on a large scale for many years, and the first compilation of these taxa from the state is provided in this study. Echinoderms now are known from 25 formations that are exposed throughout the state. The echinoids are better documented and described than the other classes of echinoderms, yet even the echinoids were poorly known from some epochs, most notably the Miocene. Previously published information showed echinoid diversity decreasing significantly from the Eocene into the Oligocene, and continuing to decline into the Miocene. Our research shows the echinoid diversity does not drop from the Oligocene into the Miocene, but instead increases by at least five species. This marked change in alpha diversity during the Miocene is a result of careful examination of smaller size fractions of sediments, which contained fragmented components of echinoids such as test plates and spines, and the diligent collecting of moldic samples, which produced additional taxonomic and stratigraphic records. The record of other echinoderms is still poor, but fine-fraction sediments also have produced disarticulated ossicles of crinoids, asteroids, and ophiuroids from several formations that had no previous record of such echinoderms. The diversity pattern of echinoderms from Florida is a reflection of both intrinsic and extrinsic factors that affect (in varying degrees) the echinoderm-bearing formations from the Paleogene through the Neogene. One of the most influential appears to be collector bias against recovering incomplete echinoderms. Many of the new species or new records of taxa from stratigraphic units in the state are based on fossils that are poorly preserved or incomplete. Other biases include over-splitting of taxonomic groups, stratigraphic unit revisions, taphonomy, and preservation potential variation in carbonate versus siliciclastic environments. Significant refinement of the echinoderm biostratigraphy and diversity patterns has occurred due to detailed examination of field samples, museum collections, and literature reviews, as well as accounting for biases inherent in the fossil record of Florida.

This paper presents the first long Quaternary palynological record from the Otway region of Victoria, an area which is biogeographically important in that it is an outlier of the southeastern highlands containing distinctive forest vegetation with great similarities to the island of Tasmania. The record is derived from a small remnant patch of cool temperate rainforest dominated by Nothofagus cunninghamiisurrounded by tall open eucalypt forest. Three clear phases are identified: an older rainforest phase dated to beyond 40,000 years BP which probably represents the latter part of Oxygen Isotope Stage 5; a phase of more open vegetation which covers at least part of the last glacial period; and a younger rainforest phase of Holocene age. The record is significant in providing refinements to late Quaternary climatic estimates from southeastern Australia utilising the climatic profiles of key rainforest taxa, and in indicating the likely presence and nature of a glacial rainforest ‘refugium’. The occurrence of a major rain forest tree, Phyllocladus,during the early forest phase and of the subalpine taxon Gunnera,during the last glacial period, taxa now restricted to Tasmania, demonstrates an even greater biogeographic link to this island in the recent past. Their extinction on the mainland is consistent with the general demise of cool temperate taxa with close Gondwanan affinities on the Australian mainland through the Late Cenozoic period. Their late disappearance contributes to the growing list of mainland extinctions of ancient and geographically interesting taxa adding weight to the proposal that Aboriginal burning has had a substantial impact on the Australian landscape during the last glacial cycle.

The Plio-Pleistocene sediments of Olduvai Gorge, Tanzania, are well known for their records of both hominid evolution and the paleoenvironments where these early hominids lived. This paper investigates the paleohabitat reconstructions of Bed I and Lower Bed II of Olduvai and provides an analysis using bovid tribes as habitat indicators. The habitat inferences based upon the bovids are compared with paleoenvironmental reconstructions from studies of the micromammals, pollen profiles, isotope geochemistry, and geology. These various habitat indicators are shown to corroborate each other closely with regard to both the kind of habitat present and the timing of inferred habitat change. The general agreement on habitat types appears to present especially strong support for the paleoecological reconstructions of Bed I and Lower Bed II. Paleohabitats ranged from closed woodland or forest to a mixture of open woodland and grassland to open grassland. The pattern of paleohabitats through time supports the idea of a climatic trend towards greater aridity, but with intermittent shifts to more humid conditions. The Plio-Pleistocene climatic history of the Olduvai basin may prove useful in understanding the evolution of East Africa climates.