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Why didn't Aborigines build cities?

Humans built cities in a relatively short period of time after their arrival in South America 10,000 or so years ago. Not only was South America a land of plenty, the humans were able to escape the tribal raiders that were the scourge of genesis farming communities in sub-Saharan Africa.

When humans arrived in Australia 60,000 years ago, conditions may have been similar to South America and cities may have formed. There is definitely some evidence that ancient Australians had advanced technology as well as some of the refined social hierarchies typically found in a settled people. Paintings on the cave walls of the Kimberly reveal they had been building boats with rudders in excess of 20,000 years ago. Like the hieroglyphics of Egypt and South America, these paintings may have also been a form of iconography. (The exact age of the paintings is unknown. All that is known for certain is that they are more than 17,000-years-old. They could be 50,000-years-old.)

If the cities had existed, they would have fallen into ruins due to environmental destruction. Either for hunting, or to clear land for agriculture, humans engaged in wide scale burning of the bush 50,000 years ago. Burning caused a decrease in the exchange of water vapour between the biosphere and atmosphere. After the foliage was razed to the ground, rain fell and soaked into the sand or quickly evaporated under the scorching sun. In turn, a reduction in humidity decreased the number of clouds forming, and the annual monsoon over central Australia failed. Whereas once the Nullarbor Plain was home to forests and tree dwelling kangaroos, now it is desert. Likewise, Lake Eyre, formerly a deep-water lake in Australia's interior, is now a huge salt flat only occasionally covered by ephemeral floods. (1)

After the ecosystem's collapse, the Australian environment lacked all the ingredients necessary to build cities, or maintain cities. The lack of a high-yield agricultural crop was one of the biggest barriers to cities being built, or rebuilt. (South Americans had corn. Asians had rice. Europeans had wheat and potatoes.) Although such crops may have been existed in Australia, or could have been introduced to Australia, most of the seeds probably would have been devoured in the years of chaos that followed the ecosystem's collapse.

Migration between nth Australia and Asia could have introduced, or re-introduced, high-yield agricultural crops. Unfortunately, most of the Australian land had lost its capability to support the crops. Firstly, the topsoil had become thin and lacked many of the essential nutrients for crop growth. Secondly, extended droughts would have killed any crops that were not supported by advanced irrigation systems. Thirdly, eucalpytus trees were taking over and making Australia more prone to bushfire as a result. Finally, the human population had become nomadic and it would have been very difficult for one group to find fertile areas where they could escape the raiders of other tribes.

As well as lacking a high-yield agricultural crop, farming was difficult because most of Australia's animals were difficult to contain. Unlike sheep and cows, Kangaroos are not herd animals that can be easily moved to new pastures or to an abattoir. If contained with rudimentary wooden fences, they jump over the top to their freedom. Other animals such as Wombats can tunnel underneath fences while Possums and Koalas just climb over the top.

The now-extinct Diprotodon may have been suitable for farming. Weighing 32 times as much as a Red Kangaroo, it could have been enclosed in a pen and humans could have fed on its blood, milk and flesh. The Genyornis was another. A flightless bird four times larger than an Emu, it could have been enclosed in a pens and humans could have fed on its eggs, and flesh. When the megafauna became extinct; however, the potential for animal husbandry with a native animal ended as well.

Cuddle Springs in north central NSW is one place where farming may have developed. Excavations by a team from the University of Sydney have found evidence of grinding stones and possibly megafauna living alongside humans for 10,000 years. (2) The presence of 30,000-year-old grinding stones is quite unusual because they predate all other grinding stones around the world by 20,000 years. Another unusual feature of the dig is that the Diprotodon is one of the few animals that was still present at the same time as people and showed evidence of being butchered by people. If the humans were merely hunter gatherers, most of Australia's smaller animals should also have lived alongside them and shown signs of being eaten by them.

Dr Juith Field has argued that the fossil record at Cuddle Springs proves that hunter gatherers had formed a balance with the megafauna. Although Field has made no mention of farming, with a high-yeild agricultural crop, Genyornis, Diprotodons, and permanent water supplies, the region had all the necessary ingredients for a farming community to develop. If animal husbandry had developed, it may explain why the Diprotodons seemed to still be alive 15,000 years after they were believed to have gone extinct. The megafauna lived because humans were farming them. (Butchering tools have been found in association with the Diprotodons.)

The Lake Condah region of western Victoria is another place where the begginings of a civilisation may have emerged. Dr Heather Builth, a Post Doctorate Research Fellow with Monash University, has found evidence that artificial ponds were constructed across the grassy wetlands. Channels were dug to connect them and eel traps were placed in the channels. Builth has estimated that these farms could have produced enough eels to sustain 10,000 people. (3) Some circular rock foundations also indicate the possibility that stone dwellings were built and people lived in villages.

Although there is archaeological evidence of eel farming and stone dwellings, no English settlers ever recorded visits to Aboriginal villages, or seeing Aborgines live in villages. Considering that the English would have been excited to find a village of 10,000 people, and English values of the time placed great virtue on a settled existence, the lack of written records indicate that had a village existed, it would have fallen into ruin prior to the arrival of Europeans. Possibly raiders could not have been kept away or perhaps droughts forced a return to a nomadic existence. Any village lacking diversity in food production would have been very susceptible to climatic variances, and would have found it difficult to grow beyond a basic level. It's possible that tribes lived a settled existence in times of plenty, but returned to hunter-gathering when the rains failed or some kind of ocean distrubance affected eel migration. Alternatively, many of the nomadic tribes may have fought for control of the eel farms in the good times, maintained them, then abandoned them when the droughts came. As the eel farms have been dated back 8,000 years, a cycle of villages forming and then busting could have continued for thousands of years. As a result, the villages never got beyond stone huts.

Even if a village formed in Victoria, for most of Australia settled societies were not possible. Consequently, nomadic humans burnt the bush and hunted animals fleeing the flames. Later they would return to hunt the animals attracted by the green shoots. This burning of the bush further decreased the land's capability to support agriculture. When a forest is burnt, nutrients go up in flames. If rains follow, the top soil is stripped away and washed into rivers and then out to sea. In a sense, the humans found themselves in a vicious cycle. They were dependant upon burning to survive, but the burning decreased the productivity of the land in such a way that forced them to keep burning it as a hunting technique.

When Europeans first arrived in Australia, they also found farming to be very difficult as well. In 1788, six cows, a bull and a bull calf were released on some average looking grass. Rather than stay put, the cows just wandered off in search of greener pasture and were lost for seven years. Grapevines wilted in the heat. Wheat fields were raided by Kangaroos and Wombats. Bushfires destroyed entire crops, houses and communities. Colonists noted the absence of fruit bearing trees and found it very difficult to find food in the Australian bush.

Today, even with the onset of modern technology, rural communities have not thrived as they have around the world. The macadamia nut remains one of the few native plants that is commercially harvested. Crocodile is one of the few native animals that is farmed. Both are great, but not sufficient to build civilizations around.

As for farming foreign produce, most of Australia's farms have failed. The Land and Water Resources Audit (1996-97) found that 80 per cent of Australia's agricultural profits are derived from less than 0.8 per cent of its agricultural land. To put it another way, 99 per cent of Australia's agricultural land makes little contribution to Australia's economy. Many of the farms, even the profitable ones, are not sustainable with the land. Many of these farms will not exist in 100 years, let alone thousands of years like some farms in Asia. Other farms only continue to exist because the federal government has provided welfare in times of drought.

Ironically, the difficulty in farming has now made Australia one of the most urban societies on earth, with 70 per cent of the population living in the 10 largest cities. Living off the Australian land is just too difficult to build a community around.

1)Burning caused megafauna extinction (http://info.anu.edu.au/ovc/Media/Media_Releases/_2005/_July/_080705magee.asp)

2)Dinnertime at Cuddie Springs: hunting and butchering megafauna? http://acl.arts.usyd.edu.au/research/cuddie/cuddie.html

3)Life was not a walkabout for Victoria's Aborigines - www.theage.com.au/articles/2003/03/12/1047431092972.html