Evolutionary biologist Richard Dawkins has welcomed the news that religious practice in America has declined, but said those who profess to have no religion often take up "something even worse".

Speaking at a Skeptics Society Conference at the California Institute of Technology in a video shared by Raw Story, he said: "One of the problem is that the so-called 'nones' often give up religion for something even worse," and jokingly added "they take up Deepak Chopra or something like that."

He was responding to a report released by Pew Research in May which showed that that while 7 out of 10 Americans still identify with a religion, the number professing 'no religion' has grown to 56 million, making the 'nones' group the second largest behind evangelicals.

The findings are based on the 2014 Religious Landscape Study of 35,000 people. A previous survey was conducted in 2007 and the 2014 study was designed to be comparable.

Remarking on the increase in the number of people with no religious affiliation Dawkins said "that's very good news" although he quipped that 'nones' unfortunately sounded rather too much like 'nuns'.

Deepak Chopra, who is co-founder and chairman of the Chopra Center for Wellbeing, doesn't feel too warmly about Dawkins either. "With Dawkins, I am just p***** off... by his arrogance and his pretense of being a really good scientist. He is not," Chopra said in an interview with Salon last year.