Migration to Sahul — Notes, Quiz, and Practice Test Summary & Study Notes

🌍 Out of Africa

Around 100,000 years ago, changing climates placed pressure on human groups in Africa. This prompted waves of migration out of Africa into Asia. These movements are central to understanding how humans reached Sahul (the mega-continent made up of mainland Australia, Tasmania and New Guinea). Archaeological finds such as human remains and teeth, analyzed with DNA and dating techniques, help establish timelines for these migrations.

🧭 Southern Dispersal Model

The Southern Dispersal Model proposes that early modern humans moved from Africa into the Middle East and then along southern Asia, through South-East Asia and into Oceania. Evidence from Fuyan Cave in Daoxian, China (human teeth dated to about 80,000 years ago) supports early presence of Homo sapiens in Asia, providing context for later movements toward Sahul.

🗺️ Sunda and Sahul: Two Palaeo-continents

During the Ice Age, sea levels were much lower. Two large landmasses existed: Sunda to the northwest (including islands now known as Java, Bali, Borneo and Sumatra, connected to mainland South-East Asia) and Sahul to the south (mainland Australia, Tasmania and New Guinea). Lower sea levels created exposed land or reduced sea gaps, but there was never a continuous land bridge between Sunda and Sahul.

⛵ Crossing the Seas — Boats and Navigation

Because of the remaining sea gaps between Sunda and Sahul, early humans must have used vessels and navigational skills to cross open ocean channels. In places where sea levels were lower, shorter sea crossings or temporary land bridges made travel easier. The need to plan and navigate deliberately indicates advanced maritime能力 and cognitive skills among these early peoples.

🚶 Migration Super-highways and Secondary Routes

Archaeological evidence shows people likely used predictable routes to move across Sahul. These are called migration super-highways and often follow coastlines and waterways, where food and freshwater were abundant. From these coastal highways, people later moved inland creating secondary routes. Features like the Gulf of Carpentaria were once large freshwater lakes, guiding early movement and settlement.

⏳ Timing and End of Migration

Current evidence indicates humans reached Australia at least 65,000 years ago. The end of the last Ice Age (around 8,000 years ago) caused ice sheets to melt, raising sea levels. Rising seas submerged land bridges and widened sea distances, which made further large-scale movement between these landmasses much harder, effectively isolating populations and ending that phase of migration.

🔎 How Archaeologists Reconstruct Routes

Researchers use a mix of methods: mapping archaeological sites with human remains and artifacts, dating techniques (such as radiometric dating), palaeoenvironmental reconstruction (to infer past coastlines, lakes and climate), and genetic analysis. Where direct archaeological evidence is absent, scientists may infer pathways by connecting known sites, known resource locations, and plausible travel corridors.

📝 Practical Skills: Map and Paragraph Tasks

Key classroom tasks include labeling Sunda and Sahul on maps, drawing migration arrows from Sunda to Sahul (using different colours for sea crossings and land travel), marking migration super-highways and at least two inland secondary routes, and annotating arrival dates. A paragraph response should describe the stages of migration, key dates, the role of climate and sea-level changes, and why migration eventually stopped.

❓ Big Ideas to Remember

• Sahul = Australia + Tasmania + New Guinea during low sea levels.
• Sunda = connected South-East Asian islands and mainland.
• Humans used boats and navigation to move between landmasses.
• Super-highways followed coasts and waterways; secondary routes moved inland.
• Rising sea levels at the end of the Ice Age changed landscapes and halted easy movement.