With the theory of Aryan invasion to the Indian sub continent in the pre-historic times no longer being acceptable, the reasons for demise of the Indus-Ghaggar civilizations after flourishing over several millennia remained a great puzzle for the historians and the archaeologists till now. A report of a study, published on 28th May 2012 in the Proceedings of the National Academy of Sciences and lead authored by Liviu Giosan, a geologist with Woods Hole Oceanographic Institution (WHOI) claims that they have found the answer to this riddle. I have described in details, the findings of this research team in an earlier article, which anyone interested can go through. However, for sense of continuity, I am repeating here, some of the main observations from this report.
Before massive human habitation of Indus-Ghaggar civilizations had settled in, for previous ten thousand years, wildly flowing river Indus and its tributaries had deposited rich soil sediments on stretches between them. The research team led by Giosan has been able to discover a massive mega-ridge 10 to 20 meters high, over 100 kilometers wide, and running almost 1000 kilometers along the Indus, in this mounded plains. It has been named as “Indus mega-ridge,” as it was constructed by the river itself with sediments deposited along it’s entire lower course. Remains of Harappan settlements, which are found today are not buried underground in this ridge but rather lie at the surface of the ridge.
The monsoon rains that brought floods to the rivers, actually started declining with time. Weakened monsoon rains and reduced run-off from the mountains, helped in taming the wild Indus and its Himalayan tributaries, so that agriculture along their banks became possible. As a result, human settlements bloomed along the Indus and its tributaries from the coast to the foothills of the Himalayas. The weakened monsoon rains created a window of about 2000 years in which Harappans took advantage of the opportunity and a great civilization arose on the banks of Indus and tributaries. Indus civilization, was built on bumper crop surpluses along the Indus and the Ghaggar-Hakra rivers from this earlier wetter era and required a huge concentration of workforce. This workforce requirement developed into great urban centers like Mohenjodaro and Harrapa.
As monsoon weakened progressively, this window of prosperity began closing and widespread aridification of the lands, where plenty of water was available earlier, drove the Harappans eastwards east or towards Ganga river by 1500 BCE, where monsoon rains remained reliable. The economic structure in the east with local rain-fed farming and dwindling streams could only support smaller agricultural surpluses and could not support large cities of Indus civilization. The cities collapsed and with them the urban arts such as writing. The population in Ganga basin now dispersed in small agricultural communities, survived and even diversified.
The study also reports another major finding, which solves the riddle of Sarswati river. Archeological evidence suggests very intensive human settlements during Harappan times in the basin of Ghaggar-Hakra river, which is believed to be the long lost Sarswati of the Vedas. The geological evidence like presence of sediments, topography discovered in this study shows that these rivers were indeed sizable and highly active in this region, most likely due to strong monsoons, during Harappan period. However these rivers were not Himalaya fed rivers. There is no evidence of waters of nearby Himalayn rivers like Satlaj or Yamuna flowing in this river. The study therefore suggests that Sarswati or Ghaggar-Hakra river was a monsoon fed perennial watercourse and the aridification reduced it to short seasonal flows like at present. but most likely due to strong monsoons.
However some Indian scientists do not agree with this analysis. They feel that the Sarasvati river system can be considered as a separate entity and not as a part of the Indus basin. It dried up a few thousand years back, due to tectonic movements, tributary diversions and climate changes. This thesis is now well documented and accepted by almost all, barring a few skeptics. The dry courses of the main river and its tributaries are at present covered with sand, loam and silt, deposited by wind over last few thousand years. They could be discerned only after the advent of remote sensing techniques. (Sankaran, A.V., 1999; Roy and Jakhar, 2001).
I would only like to add that whatever may be the actual reason, end result happens to be the same.
In addition to shifting of monsoons, Harappan cities in the south like Dholavira faced another natural calamity. The archaeologists excavating Dholavira have already found out the damages caused by a massive earth quake. Similar earthquakes must have changed the entire geographical structure here and a region once extremely fertile became an arid and marshy zone. As Giosan suggests, the populations of the Indus civilizations of the south must have simply dispersed to further south (Gujarat) and the east (Rajasthan), where better weather conditions must have prevailed.
Some of the archaeologists suggest that the Saraswati or Ghaggar river, once emptied itself into Arabian sea just, north of Rann of Kutch, what is called as Kori creek today. If this was the case indeed, one can imagine, how fertile and prosperous the region around Dholavira and Surkotada must have been.
Two years before, I paid a visit to the National Museum in New Delhi. This museum has a great collection of many items and artifacts from Indus civilizations. I found that a number of things like bullock cart designs, kitchen utensils, toys were very similar to what was in use even about 50 years before, in India. To me, Indus civilization legacy to Indians is not lost but continues even today.
The then director general of the Archarological survey of India, Mr. Braj Basi Lal had addressed a gathering in the Indian city of Bhopal, arranged by National Council for Education, Research and Training (NCERT) in November 2002. In his speech, Mr.Lal had highlighted the similarities between Harappa culture and The present Indian culture. I quote:
” whichever walk of life you talk about, you will find in it the reflection of the Harappa Culture: be it agriculture, cooking habits, personal make-up, ornaments, objects of toiletry, games played by children or adults, transport by road or river, folk tales, religious practices and so on. Here we give just a few examples. The excavation at Kalibangan has brought to light an agricultural field dating back to circa 2800 BC. It is characterised by a criss-cross pattern of the furrows. Exactly the same pattern of ploughing the fields is followed even today in northern Rajasthan, Haryana and western Uttar Pradesh. Today mustard is grown in the widely-distanced furrows and chickpea in the narrower ones and it is most likely that these very crops were grown in a similar manner during the Harappan times; we do have evidence of both these items from the Harappan levels. Kalibangan has also yielded a linga-cum-yoni of the same type as is worshipped now. This very site, along with Banawali, Rakhigarhi and Lothal, has brought to light ‘fire-altars’, indicating rituals associated with fire. ”
Some other parts of Mr. Lal predicts a totally different course of history, but is is better to leave it to the experts. What I find important here is the thought that Indus-Sarswati civilizations never really were wiped out but rather continued in other parts of India with blooming of the Vedic culture.
Now we come to the last point regarding adoption of Vedic religion by India somewhere in second millennium BC. There are serious differences of opinion between historians about exact plave of origin of the Vedic culture. Historian Romila Thapar along with others believe that Vedic religion originated in Marginia/Bactria region of northern Afghanistan, whereas Mr. B.B. Lal, whom I have mentioned above believes that Vedic culture originated on the banks of Sarswati river. Whatever may be the place of origin, the real point of interest is how this new religion managed to uproot the Lingam and fertility idol worship of the Harrapans with a vedic religion, which had no idols. I want to compare this to more modern adoption of Buddhism by many countries in Asia such as China, Japan, Korea and Thailand. Around 300 BCE, Indian emperor Ashoka sent Buddhist monks all over Asia to spread this new religion. There was no question of forcing anyone or no coercion. Yet we find that these countries adopted Buddhism. I feel that Indians must have adopted Vedic culture in this fashion, still keeping some elements of Indus religions and cultures in the new religion. The best examples of this could be the retaining of Durga or the mother goddess and Lingam, now associated with Rudra (an original Vedic God) in the new culture.
A recent genetic study by India’s Council of Scientific research suggests that modern humans have migrated to India from three origins: the central Asia, Malaysia and Andaman islands. It is quite likely that the Indus civilization people came there from central Asia, settled down there for 2 or 3 millenniums and later, when things became tough, again moved eastwards and southwards. Indus civilization never really saw it’s demise. It just moved eastwards and southwards.