There is pollen evidence from the Horton Plains for  herding and the farming
of barley and oats by 15,000 BC and also around  8,000 BC. The new evidence
from the Horton Plains  is of great importance. Ghar-i-Mar and Aq Kupruk in
Afghanistan and  Mehrgarh in Pakistan were known to have had a Neolithic
subsistence  strategy by 7,000-6,000 BC. There is tentative evidence of herding in
northern Rajasthan by 7,000 BC, of rice and pottery at Koldihwa, U.P. in  India
by 5,000 BC, and perhaps cereal management/farming in the Nilgiri  Hills of
South India by 8,000 BC. Therefore  Lankans had proof of Agro subsistence
strategy 7000 years before the world  did.
Even if they found hearding  started 10 millineum before this, it still is
not enough time for the  human body to adjust to this new food source.