The archipelago of the Andaman and Nicobar islands consists of 572 islands; 35 are known to be inhabited. These are home to five tribes. The Jarawas, Sentinelese and Onges are Negrito tribes. The Andamanese have ceased to be a tribe and a pure-blood Andamanese is a rarity. The remaining two are mongoloid tribes, the Nicobarese and the Shompen. After the earthquake and the subsequent tsunami, a Coast Guard chopper flew over Sentinel to make sure the Sentinelese were all right. The tribe has never had any contact with 'civilisation' and previous attempts to land there have been met with arrows and stones. "As the chopper went down a bit, they camerunning on to the open beach and started throwing stones and shooting arrows," said Coast Guard Director-General Y.S.M. Aran Kumar Singh. That is probably an indication that the tribe has survived the disaster. But the tsunami has washed away the beach. Samir Acharya of the Society for Andaman and Nicobar Ecology thinks this may have a long-term impact on the lifestyle of the Sentinelese, who are fisherfolk. "They might shun fishing altogether," he says. "It's impossible to push a boat across a mud flat. One has to wait and see." Anjan Biswas, pradhan of Ramkrishnapuram in Little Andaman, says the Onges ran into the jungle as soon as they saw the sea receding. "They ran till they reached our village," he says. Of the 98 Onges, 73 are in a relief camp at the village. There is no news about the rest as they were in a reserve in another part of the island. The local administration sent an 18-member team to assess the condition of the 266 Jarawas who live in the 800 sq. km Jarawa reserves in South Andaman. "They could not be located but it is not to be taken seriously," says Acharya. "I'd rather wait for information. The Jarawas and Onges are similar in many ways. It is likely that the Jarawas also sensed danger and ran inland." There is no news from the 150-odd Shompens as nobody knows what things are like in Great Nicobar beyond Campbell Bay. The roads have been washed out, and bridges and culverts broken. The more numerous Nicobarese, who live in Car Nicobar and Katchal, have borne the brunt of the tsunami.