Hello everyone, and welcome to Brains Matter s 24 th show for the 18 th of April, 2007. On today s show, I ll be talking about one of the oldest acknowledged civilisation in the world - the Indus Valley Civilisation. Brain Teaser I ll start with a brain teaser what did Arno Penzias and Robert Wilson discover in 1965, and subsequently receive the 1978 Nobel Prize for Physics for? The answer to that later in the show. IVC In the 19 th century, India was regarded as the mother of civilisations. Some archaeologists thought that it was a derivative of Mesopotamian civilisations, before they looked deeper and realised that it was indeed, a very unique civilisation. During archaeological excavations, they found nothing at all resembling Mesopotamian artefacts, but instead, uncovered huge cities. The cities and civilisation I m talking about is the Indus Valley Civilisation. It gave rise to the Indian cultures of today, and was based around north-western India, and modern day Pakistan. It is generally accepted that the Indus Valley Civilisation reigned from about 3300 BC to around 1700 BC so almost 5,500 years ago but as you ll hear later on, some evidence points to the fact that this may have extended back to around 9,000 years ago. Along the Indus Valley region, over 1000 sites and cities have been found. The Indus Valley Civilisation was based, as it s name suggests, around the banks of the Indus River. It spread south to the Arabian Sea coast of India, as far west as the Iranian border, north towards the Himalayas, and to the south and east well within modern day India. The major cities in this civilisation
included Harappa, and it is still called the Harappan Culture today in honour of that city, Mohenjo-daro, and Lothal, amongst others. Another name for the civilisation is the Harappan Civilisation and it was named this after the first city that was excavated, called Harappa. Sometimes it s called the Indus Ghaggar-Hakra Civilisation, or the Indus-Saraswati Civilisation these names come from the Ghaggar-Hakra River, which is thought to be the ancient Sarawati River of the Rig Veda. I ve spoken of the Vedic cultures and Vedic science in previous episodes. Some sites covered 200 300 hectares, and Mohenjo Daro was probably the largest. Mohenjo Daro was founded around 2600 BC It had around 40,000 people and an area of around a square km. It is recognised today as one of the oldest, and most important cities in the Indus Valley Civilisation. It is one of the world s first large cities and is contemporary with other ancient cities in Mesopotamia and ancient Egypt. Today, it s listed as a UNESCO World Heritage site. It is thought that the city of Mohenjo Daro was the administrative centre of the Indus Valley region, and it was one of the most well planned and engineered city in the ancient world. Archaeologists believe that the Indus Valley Civilisation may have been home to over 5 million people. The streets reflect the ingenuity of the planners, and the city layout was distinguished by a criss cross pattern long straight roads, making it easy to navigate. The main road was never less than 9 metres wide.
The entire city had a complex water management system, and 80 public toilets. Residences had a tiled bathroom and their own well. Sewers serviced the whole city, and drains, gutters, and waste water had ducts dug into the street. They even had public bins made of brick, and emptied at regular intervals. The houses were protected from noise, odours and thieves, and what is recognised as the world s first urban sanitation system. Homes had their own wells, or groups of homes shared a well. Houses had tiled rooms set aside for bathing, and waste water was directed to covered drains, which linked up to the public drain system I mentioned just now. Houses opened to inner courtyards and smaller lanes, and some houses were double storey in height. At the top of the city on a huge platform, there was a huge bath or pool built. The bath had a layer of natural tar to prevent it from leaking, and the centre of the bath building had a swimming pool. Public buildings in most Harappan cities suggest a high level of civic duty and organization. The city granary at Mohenjo-daro is designed with bays to receive carts delivering crops from farmland outside the city, and there are ducts for air to circulate beneath the stored grain to dry it. Mohenjo-daro didn t have large city walls, but had towers to the west of the town centre, and fortifications to the south. It is thought that Mohenjo-daro and Harappa were an administrative centres. Harappa and Mohenjo-daro otherwise share pretty much the same architectural layout, and weren t heavily fortified like other Indus Valley Civilisation cities.
Archaeologists believe that Mohenjo-daro was destroyed and rebuilt at least seven times the reason for this being the flooding caused by the Indus River. What they found was that each time the city was destroyed, a new one was built on top of the old ones. The Indus Valley region of ancient India covers an area twice as large as France. Dholavira in western India was another city in the IVC. In Dholavera, archaeologists discovered brick and stone walls, up to 15 metres tall. They used Himalayan cedar and the city also used a complex water system, with water collected in conduits, which ran off to outside the city limits. Since it was discovered in 1989, Dholavira has been slowly excavated and has given clues to the technological innovation of the discoverers. They ve found deep pits in Dholavira, but weren t able to determine the purposes of these pits. They go deeper than 8 metres from the surface of the city. How were such walls built with the stones fitting exactly, at such a time? It s significant in the fact that it is one of the first if not the first example of rock architecture, not just by the Harappan cultures, but of any cultures in the world. The pits turned out to be reservoirs something that archaeologists only figured out recently. Dholavira s city plans were reconstructed by archaeologists, and they figured out that the reservoirs that surrounded the city held over 250,000 litres of water which in today s world would be seen as extremely valuable, especially in Australia with it s water restrictions. The city covered 48 hectares with a population of 20,000. The city had gardens, warehouses, and granaries, and had wheat and barley as it s main source orf trade.
How were the reservoirs around the city filled? Especially with so much water, around 4000 years ago? Drinking water has always been scarce in the marshes around the Kush region most of it is salty. Yet the IVC survived in that region 5000 years ago, with the most advanced civilisation in the world at the time. Dry river beds around Dholivera, which become harsh torrents during the monsoon season, they found stone structures dams to direct the flow of water. This is how they captured enough water for the residents of the city. The water needs were quite high, because they even cleaned the streets with water as well. The people of Dholivera changed the course of the water to fill out their reservoirs. For the water to flow from one reservoir to the other, they used the natural incline of the land very advanced design and thinking. There was a 13m difference in height from the reservoirs from the top end of the city to the bottom end of the city.. The city was designed around the collection of water. Today, the ruins have no water, and look as though they exist in the desert. Pretty amazing. They also had ingenious systems to collect rain water something we need to have more of today! Gutters channelled rainwaters into a large reservoir just outside the city. Water allowed plants/ crops to grow, it allowed the purification of souls. Water was worshipped as one of the major elements of the world.
In the IVC, it makes sense that most of the cities lie along the Indus River, but archaeologists have found that many of the cities today aren t anywhere near the current Indus river, but in sandy desert or towards the Himalayas, far away from the Indus River. Why is this the case? Archaeologist think the answer to this lies in an Indian folk song. The Ghaggar-Hakra once flowed through the Thar Desert, and was thought to have been just folklore, but today there appears to be evidence of it s existence. Satellite imagery, the soil type which indicates a dried up riverbed. It was said to have started high in the Himalayas, which went down through the Thar desert of today and this is the river that serviced the Dholivera patrons. In 1990, new wells were dug to obtain water for farmlands and this was groundwater that flowed along the path of Ghaggar- Hakra 4000 years after it disappeared from civilisation. Trade and ideas spread over the years. Stonemasons created new tools such as jasper tools, and tools to polish stones. They made ornaments and mirrors, and excelled at woodwork. Their ceramics were traded across the east they mastered copper, bronze, and gold for jewellery and the IVC seemed to be on the verge of industrialisation especially Mohenjo Dharo and Harappa. Textiles, processed foods and who knows what else, but all of that has been lost. Their goods were exported widely, including to the gulf of Mesopotamia. The items used for trade were stamped with identification markers for the Harappan cultures. The Indus merchants invented the idea of contracts using cylinders to mark out the contracts, which were also used in Metosopotamia, carved with animal profiles, with inscriptions accompanying the pictures.
Archaeologists can t decipher the writing from the IVC though, since most of the writing was done on perishable media apart from street signs and some contracts, so there isn t enough information for today s archaeologists to figure out what the writing means. In 1989, in Dholavera, an inscription made out of quartz was found. They thought ti might be the equivalent to the Rosetta Stone, but it was only a few signs so today, we are no closer to understanding the writings of the IVC as last century. The signs at the front of the city appeared to have wheels in it so some think it may be one of the earliest examples of traffic signs at the entrance to the city. The Harappans also had knowledge of dentistry it seems about six years ago, archaeologists who were studying the remains of a couple of men from the early Harappan period knew about fixing teeth. In 2006, the journal Nature announced that there was evidence of the Harappans drilling in teeth, while the person was alive, from the Neolithic period the oldest ever discovered and it dates from 7,500 9,000 years ago. The system of government hasn t been worked out yet was it a modern political system? Was it ruled by a sovereign or prince? Or perhaps even priests? Trade was via the ocean, to the Arabian Peninsula across the Arabian Sea even over to Abhu Dhabi in the Persian Gulf. Merchants from the IVC tended to go there to trade. How did they trade with their totally different language and cultures? A Sumerian text found in 2000BC found mention of a translator who spoke both the languages of the Indus and Sumeria (Mesopotamia). Shame he didn t leave a dictionary in English!
At about 2000BC, the IVC started to disappear the large cities were slowly abandoned because of the equivalent of globalisation people started to live differently and move away from singular large cities. The IVC empire literally fell apart, and the industries and cultures changed although some of that heritage is still preserved in modern-day India. There are temples in India where carved in the rock at the base of the buildings are wells exactly the same way that wells and water were worshipped in the IVC. Mohenja-daro, Harappa, and the IVC disappeared without a trace from history until it was rediscovered in the 1920s. Perhaps this is why many discoveries have been attributed to the science of Europe and China over the past couple of thousand years, rather than being attributed to origins which may possibly be from the Indus Valley Civilisations such as mathematics, trade, city planning, plumbing and aqueducts, and so forth. Perhaps one day, when the secrets to the Indus Valley s writing is cracked, these historical errors may be corrected. Brain Teaser Answer The answer to the brain teaser what did Arno Penzias and Robert Wilson discover in 1965, and subsequently receive the 1978 Nobel Prize for Physics for? The answer to that is the Cosmic Microwave Background or the electromagnetic remnants of the Big Bang. Listener Feedback And now for some listener feedback. Firstly, I had an email from Kerry Lynch I m not 100% sure where on the globe Kerry is from, but she had some comments about the episode on the episode where I talked about the definition of Scientific Theory, and used evolution as an example. Kerry mentioned her belief in
an Intelligent Designer, and asked if I wanted to know her views on it, and will hopefully forward those views through. Next up was a couple of emails from Pilar Gallardo, a chemical engineer, from Melbourne in Australia. Thanks for your emails Pilar, and thanks for your topic suggestion I ll be following that up for an upcoming episode. I might have to devote an episode in the near future on topics suggested by listeners! A hello to Terri Collis from Melbourne, Australia, who mentioned the sound mixing I trust it s improved in your eyes or should that be ears? Steve Parfitt from Adelaide in Australia writes: I have to say that I enjoy the topics you cover and the interesting and intelligent dialogue you have with guests. Glad to hear you re not bailing out on us. Quality programs as yours are few and far between. Looking forward to many more episodes Steve, I hope to have more guests in the near future as well, so that s something to look forward to. Thanks for your feedback and kind words. Mike Gelhausen from Dallas, Texas writes: Thanks for your podcast. I listen weekly as a way to stay in touch with the fast-changing world of science as well as to update my general science knowledge. Being 50 years old, I ve been out of school for quite awhile, but have worked in a technical field. I ve recently retired from the commercial world and am involved in K-12 education, focusing on science, math and technology. Also, my son is studying engineering and genetics so I read and listen to many offerings. Brains Matter is on the list. Keep up the good work! Thanks for your email Mike. It s good to hear that you re involving yourself in education, and looking specifically at science and maths. That s what we need more of! So good work!
Pin of the Episode Today s Pin of the Episode goes to Nathan, from Queensland in Australia. Thanks for signing the frappr map on the Brains Matter web site, Nathan. That brings me to the end of another episode of Brains Matter. You can check out the Brains Matter website at http://www.brainsmatter.com/, and you can find all the previous episodes of the show there. Just click on the podcasts link on the right hand side, and choose whichever episode takes your fancy. There s also some other information on the web site, so check it out. If you have any comments or suggestions, feel free to leave a message on this episode s entry at the website, or to send me an email at mail@brainsmatter.com You can find the podcast in itunes, or by subscribing manually via the link on the web site. Please vote for the podcast in Podcast Alley there are links on the site and don t forget to vote every month, since the votes reset each month. If you want to support the show, you re also welcome to make a donation via the paypal link on the web site as well. I ll leave you with a quote from Ben Hecht. Trying to determine what is going on in the world by reading newspapers is like trying to tell the time by watching the second hand of a clock I hope you enjoyed the show. Bye for now.