Maintaining that there was no scientific evidence of the man-made structures in the Adam's Bridge area, a top Marxist leader has accused the Bharatiya Janata Party of taking recourse to faith to authenticate mythology as history and communalising Setusamudram and other issues to gain political advantage.

Communist Party of India-Marxist leader Sitaram Yechury said the BJP, which had first sanctioned the Setusamudram project while in government, has been thoroughly exposed in its "diabolical opportunism" by opposing the same project for "political benefit through disastrous communal polarisation."

In an article in the latest issue of its party organ People's Democracy, he said the Constitution, while protecting the right of the individual's choice of faith, also seeks to encourage scientific enquiry and spirit.

"These cannot be and should not be counterpoised," he said.

Giving a "materialistic" interpretation to the dasavataras, Yechury said this could be seen as "a remarkable recording of the evolution of human life and its civilisational advance."

Referring to fish -- the first avatara, he said science has now confirmed that the first life forms evolved underwater.

Then came the tortoise representing the amphibian, capable of living both on land and in water.

This was followed by the boar which lived only on land. The next avatara was the Narasimha reflecting transition from the animal to the human form.

The vaman avatara came next representing the evolution of human form in dwarf size, which is followed by Parasuram who wields the axe as his weapon, symbolising the stage of clearing forests for human settlement, the CPI-M leader said.

After Parasuram came Ram, the avatara who wields the bow and arrow, a weapon that can protect human settlements by attacking the enemy from a distance, he said.

Balaram came next wielding the plough, signifying evolution of human civilisation to the agrarian economy.

Krishna, who comes after this stage, symbolises the domestication of the cow and development of the dairy economy.

Kalki, who is yet to arrive, is portrayed as riding a horse representing the stage of domestication of the horse, as the Aryans mastered and majestically moved across lands, Yechury said.

"Thus, without entering into any dispute on matters of faith, this remarkable materialist interpretation of the dasavataras, surely merits attention.

"Faith in its quintessential form must facilitate the pursuit of truth and acquiring the ability to recognise the truth. Faith must encourage the adventure of ideas and promote scientific enquiry and not reduce itself to fanning communal passions for petty political and electoral benefits," the CPI-M leader said.