The hypothesis that long-term nutrient poverty in Australian soils led to intense fires explains many fire responses of Australian species, as does the near-global evidence for fire during the Cretaceous. The Neogene drying of Australia allowed the rise to dominance of some important components of the extant fire adapted taxa that originated in the Late Cretaceous, but were not prominent in the rainforest-dominated Palaeocene.

Numerous Australian plants show fire-adapted traits that may have evolved in the Cretaceous. Fossil evidence of Cretaceous fires elsewhere on Earth has been much better known than in Australia, but we confirm that Cretaceous fire evidence does occur widely in Australia. Cretaceous burning reasonably influenced the evolution of modern Australian environments, with the most interesting evidence being the success of members of the Proteaceae family, lineages of which were important in burnt, open habitats at least 70 million years ago.

The extrapolation back in time of characters found in living species and populations to their common ancestor suggests that the eucalypts, and possibly the fire-adapted traits that now allow eucalypts to dominate sclerophyll forests and woodlands in Australia, had evolved ~65 million years ago. This is some 12 million years earlier than the oldest known eucalypt fossils. Our paper identifies reasons underlying this discrepancy and suggests ways this might be resolved.

Eucalypts dominate the Australian vegetation today and thrive in a high fire frequency environment. Their macrofossil record suggests they originated in the Weddellian Biogeographic Province, around the Cretaceous–Paleogene boundary, in an area with high natural fire frequency and some dry periods when flammable fuel could accumulate.

The Late Oligocene to Mid-Miocene brown coals of the Gippsland Basin in southern Victoria preserve a rich botanical suite of macro- and microfossils, sometimes associated with fusinite or fossil charcoal remains. Detailed pollen and macrofossil analyses have identified many plant taxa with affinities to modern genera and families that are associated with the charcoal deposits. The palaeobotanical and geological setting for the deposition of these ancient Tertiary peat mega-swamps is outlined against a background influence of fire in a mesothermal climate, with the likelihood of a pronounced seasonal influence.

How Aborigines shaped the Australian environment with fire has been fiercely contested by historians and ecologists. The present paper uses ecological theory, and historic archives to review and test our understanding of the role of Aboriginal burning in temperate grasslands. Fire-stick farming for the production of staple roots was likely instrumental in grassland formation and maintenance, and implies targeted management that affected the structure and function of temperate grassy ecosystems.

The arrival of people did not itself cause large extensive change in fire regimes in Pleistocene Australia. However, people caused megafaunal extinction, and this resulted in dramatic changes to fire and vegetation, but only in some environments.

The critically endangered Wollemi pine is the sole remnant of an ancient lineage with extremely low, and previously undetected, genetic variation. Advanced genomic techniques enabled the detection of genetic diversity at two sites. This information is critical for ex situ preservation of this charismatic species and highlights the simple application of new technologies to biodiversity conservation.

The spider orchids (Caladenia) of Australia comprise the largest single terrestrial orchid genus, with >300 species, however many are threatened in their natural habitats – including the grand spider orchid (C. huegelii). We report on development of successful tissue culture and cryopreservation protocols for off-site (ex situ) germplasm conservation.

Tree height control is important in the management of macadamia orchards. Hedging the tops of the trees is quick and cheap, but brings with it a large yield penalty. We show that hedging only half the tops of the trees has much less of a yield penalty and restricts the regrowth.

Long-lived seed banks provide the ability for many plants to survive extended periods of drought. The failure of P. spinescens (a key wetland plant in Barmah Forest) to germinate post-drought was found to be implicated with the lack of a viable long-lived seed bank. For this species in this system, regeneration from stem fragments and rootstock may be more important than germination from seeds.

Australia’s native baobab, Adansonia gregorii, is the only baobab tree outside the African continent and is thought to be hawkmoth-pollinated. The aim was to identify major pollinators. The results of the current study show that the tree is mammal-pollinated, with the black flying fox (Pteropus alecto) as the main pollinator.

The rare Pilbara species Aluta quadrata is found in three geographically separated locations in the Hamersley Range, and a genetic study identified a moderate to high contemporary differentiation among locations, but low historical differentiation. The differences among locations suggest the use of local seed sources for augmentation or establishment of new populations, as may be required to manage impacts from mining operations.

Three plants from Neotropical savannah were evaluated at two altitudinal areas, separated by 700 m. The leaf anatomy, the quantum yield of photosystem II, and the photosynthetic pigments were taken during the rainy season. High structural modifications and low physiological alterations were apparent, showing that the abiotic factors appear to modulate the plastic responses of plants across altitude.

Investigation of genetic and morphological differentiation in tree and multi-stemmed forms of tuart (Eucalyptus gomphocephala) showed no genetic differentiation associated with growth habit, but there were some morphological differences in buds and fruits. The differences in growth habit in fragmented populations at the northern end of the distribution on the Swan Coastal Plain in Western Australia are likely to be due to environmental factors associated with harsh conditions.