The French have been doing lot of excavation in Mehrgarh (in Balochistan), home of one of the oldest farming communities in the subcontinent that existed about 8000 years ago. Mehrgarh was abandoned by the time of emergence of the Indus Valley Civilization and now findings have surfaced which link these two.

Most of the ruins at Mehrgarh are buried under alluvium deposits, though some structures could be seen eroding on the surface. Currently, the excavated remains at the site comprise a complex of large compartmental mud-brick structures.
Function of these subdivided units, built of hand-formed plano-convex mud bricks, is still not clear but it is thought that many were used probably for storage, rather than residential, purposes. A couple of mounds also contain formal cemeteries, parts of which have been excavated.
Although Mehrgarh was abandoned by the time of the emergence of the literate urbanized phase of the Indus civilization around Moenjodaro, Harapa, etc., its development illustrates the development of the civilization’s subsistence patterns, as well as its craft and trade.
Mr Jarrige said that many beautiful ceramics had been found at the site in Balochistan and were believed to be of the era as early as eighth millennium BC. The French archaeologist said that studies suggested that the findings at Mehrgarh linked this area to the Indus civilization.
There are indications that bones were used in making tools for farming, textile, and there are also evidences of the use of cotton even in that period. Mr Jarrige pointed out that the skeletons found at the site indicated that the height of people of that era was larger than that of the later period.
He said that the architecture at that time was well developed. Rice was the staple food for those people and there were also indications of trade activities. [8,000-year-old civilization in Mehrgarh proved via IndiaArchaeology]

When the urns containing human skeletons were discovered in Adichanallur in Tamil Nadu, they were initially dated to 800 BC. Now one of the urns has been dated to 500 BC and what makes this interesting is the script which was present in the urn.

The claim on the date of the script and the assertion that it is in Tamil-Brahmi will be subjected to the scrutiny of scholars in the field.
The term `Tamil-Brahmi’ is used when the script is in Brahmi but the language is Tamil. The Brahmi script was predominantly used for Prakrit from the Mauryan (Asokan) period. The Brahmi script was brought to the Tamil country in the third century B.C. by the Jain and Buddhist monks during the post-Asokan period.
According to Iravatham Mahadevan, one of the foremost authorities on the Tamil-Brahmi script: “The Brahmi script reached Upper South India (Andhra-Karnataka regions) and the Tamil country at about the same time during the 3rd century B.C. in the wake of southern spread of Jainism and
Buddhism.” In his magnum opus, Early Tamil epigraphy, From the Earliest Times to the Sixth Century A.D., Mr. Mahadevan says that “the earliest Tamil inscriptions in the Tamil-Brahmi script may be dated from about the end of 3rd century or early 2nd century B.C. on palaeographic grounds and stratigraphic evidence of inscribed pottery. The earliest inscriptions in the Tamil country written in the Tamil-Brahmi script are almost exclusively in the Tamil language.” [`Rudimentary Tamil-Brahmi script’ unearthed at Adichanallur]

Tamil Brahmi scripts have been found in the caves of Jain monks in Tamil Nadu and they were dated to 3rd century BC, thus working with the theory that Buddhist and Jain monks could have bought the Brahmi script to the south. But if the date of around 500 BC is accurate, it means that the script reached Tamil Nadu during the time of Buddha itself and not much later