The Pliocene Era: Climate Change, Evolution, and the Shaping of Modern Landscapes
The Pliocene Era (or Pliocene Epoch) was a crucial stage in Earth’s geological and biological evolution. Spanning from approximately 5.3 million to 2.6 million years ago, it marked the final epoch of the Neogene Period, immediately preceding the Pleistocene Ice Ages.
During the Pliocene, the Earth’s climate continued to cool, ocean and atmospheric systems stabilised into modern patterns, and many of today’s landforms — including Australia’s deserts, river systems, and coastal plains — took shape. In Victoria, this era saw the continued influence of volcanic activity, marine regression, and the spread of dry-adapted vegetation, setting the stage for Aboriginal Country as it exists today.
The Pliocene also holds major evolutionary significance: it was the time when early human ancestors (hominins) emerged in Africa, adapting to the new savanna environments created by global climatic shifts.
Geological Overview
The Pliocene followed the Miocene Epoch and witnessed the continued collision and uplift of continental plates.
Global Geology
The Alps, Andes, and Himalayas continued to rise due to tectonic compression (Scotese, 2015).
The Isthmus of Panama closed about 3 million years ago, connecting North and South America, altering ocean currents, and dramatically changing global climate (Zachos et al., 2001).
Ice caps grew in Antarctica and Greenland, leading to periodic glaciation.
Australian Geology
Australia had fully separated from Antarctica and continued drifting northwards, entering subtropical latitudes (McGowran et al., 2004).
The continent’s interior uplifted and dried, forming the basis of the modern arid zone.
In Victoria, the Western Volcanic Plains (extending from Ballarat through Camperdown to Portland) remained geologically active, producing new lava flows, scoria cones, and maars (Joyce, 2010).
The Otway Basin and Gippsland Basin recorded alternating marine and terrestrial deposits, marking sea-level fluctuations.
Climate and Environmental Change
The Pliocene climate represented a critical transition from the warm conditions of the Miocene to the cooler, drier world of the Ice Ages.
Early Pliocene (5.3–3.6 million years ago)
Warm and humid, similar to modern subtropical climates.
Polar ice was limited, and sea levels were approximately 25 metres higher than today (Zachos et al., 2001).
Australia remained partly forested, with rainforests along the coast and woodlands inland.
Late Pliocene (3.6–2.6 million years ago)
Marked cooling and drying; ice sheets expanded at both poles.
The onset of glacial cycles began to dominate Earth’s climate system.
Grasslands and open shrublands replaced forests across southern Australia.
Ecosystems and Biodiversity
Flora
The Pliocene saw the further spread of grasses, particularly C4 species adapted to arid and open environments.
In Victoria, fossil pollen from the Otway Ranges and Ballarat Basin indicates a shift from rainforest to sclerophyllous vegetation, including eucalypts, acacias, and banksias (Christophel & Greenwood, 1989).
These changes mirror the beginnings of the modern Australian bush ecosystem.
Fauna
Global mammalian fauna increasingly resembled modern forms: elephants, horses, and cats diversified.
In Australia, marsupials evolved larger, more specialised species:
Thylacoleo carnifex, the marsupial “lion,” emerged.
Macropods (kangaroos) adapted to open grasslands.
Diprotodontids and giant wombats became dominant herbivores.
Birds such as emus, cockatoos, and waterfowl flourished alongside lakes and rivers.
Marine ecosystems in Victoria supported whales, seals, and sharks in shallow coastal seas.
The Pliocene in Victoria
Victoria during the Pliocene was geologically and ecologically dynamic:
Volcanic Activity
The Newer Volcanics Province continued erupting intermittently. Lava flows around Mount Napier, Tower Hill, and Lake Corangamite created fertile basalt soils that later supported Aboriginal agriculture (Joyce, 2010).
Marine Retreat
Receding sea levels exposed coastal plains near Port Phillip Bay, Bellarine Peninsula, and Western Port, setting the boundaries for future human occupation.
Rivers and Lakes
Increased rainfall in the early Pliocene carved the Barwon, Moorabool, and Glenelg Rivers, still central to Wadawurrung and Gunditjmara Country.
Later drying phases reduced permanent waterways, encouraging adaptation in both fauna and vegetation.
Fossil Evidence
Fossil sites near Hamilton and Torquay contain remains of ancient whales, sharks, and marine molluscs.
Inland deposits preserve pollen and leaf fossils indicating the transition from warm, wet to cool, dry environments.
Human Evolution in the Pliocene
The Pliocene is pivotal in human history.
Around 4.4 million years ago, Ardipithecus ramidus appeared in Africa, showing both bipedalism and arboreal traits.
By 3.5 million years ago, Australopithecus afarensis (“Lucy”) walked upright, signaling the emergence of early human ancestors (Begun, 2004).
These evolutionary changes were likely driven by the climate fluctuations of the Pliocene, which favoured adaptability to open savanna environments.
While no humans lived in Australia at this time, the ecosystems forming during the Pliocene — grasslands, arid plains, and river systems — became the foundation for First Peoples’ future homelands millions of years later.
Global Context
The Pliocene world began to look like the modern Earth:
Continents were largely in their current positions.
Ocean circulation patterns established modern climate zones.
Global cooling led directly to the Pleistocene Ice Ages (2.6 million–11,700 years ago).
Pliocene global temperatures were about 2–4°C warmer than today — a point of reference for modern climate change discussions (Zachos et al., 2001).
Cultural and Deep-Time Connection
In Aboriginal cosmology, landscapes created during the Pliocene are interpreted through Dreaming stories of fire, water, and transformation. Sites such as Budj Bim, later used by the Gunditjmara for eel aquaculture, are part of volcanic plains born in the Miocene and Pliocene epochs (UNESCO, 2019).
These ancient processes — lava flows, sea changes, the creation of lakes and stone — are echoed in stories of ancestral beings shaping Country, demonstrating Indigenous understandings of geological time that parallel scientific chronologies (Rose, 1996; Neale, 2017).
Conclusion
The Pliocene Era was a time of profound transition — geologically, biologically, and climatically. It witnessed the emergence of modern ecosystems, the evolution of early humans, and the final shaping of Australia’s arid landscapes.
In Victoria, the Pliocene’s legacy can still be read in its volcanic plains, coastal cliffs, river systems, and fertile soils — features later woven into the stories, livelihoods, and spiritual lives of Aboriginal peoples. Understanding this epoch connects geological time with cultural continuity, reminding us that deep Earth history and human story are inseparable.
References
Begun, D. R. (2004). The Earliest Hominins: Morphology and Ecology. Annual Review of Anthropology, 33, 345–368.
Christophel, D. C., & Greenwood, D. R. (1989). “Changes in vegetation and climate through the Tertiary of southeastern Australia.” Review of Palaeobotany and Palynology, 58, 99–129.
Joyce, E. B. (2010). The Western Victorian Volcanic Plains: A Field Guide to the Newer Volcanics Province. Geological Society of Australia.
McGowran, B., Li, Q., Cann, J., & Padley, D. (2004). The Cenozoic of the Australian Southern Margin: Evolution of a Rifted Continent. Journal of Australian Earth Sciences, 51, 125–145.
Neale, M. (2017). Songlines: The Power and Promise. Canberra: National Museum of Australia.
Rose, D. B. (1996). Nourishing Terrains: Australian Aboriginal Views of Landscape and Wilderness. Canberra: Australian Heritage Commission.
Scotese, C. R. (2015). The Paleomap Project: Paleogeographic Maps of the Pliocene Epoch. University of Texas.
UNESCO. (2019). Budj Bim Cultural Landscape World Heritage Nomination. Paris: UNESCO.
Zachos, J., Pagani, M., Sloan, L., Thomas, E., & Billups, K. (2001). “Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present.” Science, 292(5517), 686–693.
Written, Researched and Directed by James Vegter 16/09/2025
Magic Lands Alliance
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Magic Lands Alliance acknowledge the Traditional Owners, Custodians, and First Nations communities across Australia and internationally. We honour their enduring connection to the sky, land, waters, language, and culture. We pay our respects to Elders past, present, and emerging, and to all First Peoples communities and language groups. This article draws only on publicly available information; many cultural practices remain the intellectual property of communities.