Rubio, during an interview last month with GQ, was asked how old he thinks Earth is.
"I'm not a scientist, man," he said. "I can tell you what recorded history says, I can tell you what the Bible says, but I think that's a dispute amongst theologians and I think it has nothing to do with the gross domestic product or economic growth of the United States. I think the age of the universe has zero to do with how our economy is going to grow."
Jeb Bush Jr. -- son of Republican former Florida Gov. Jeb Bush -- said on CNN the question was "strange" and Rubio's response was "kind of a head-scratching type of answer."
He said the Republican Party has been portrayed as "kind of anti-science and anti-technology" but needs to be "a kind of pro-science and pro-technology party. And I think Marco Rubio is just that."
In an interview Wednesday with Politico, Rubio said his comment to GQ "was actually trying to make the same point" President Barack Obama made in 2007 that there is no scientific debate about the planet's age.
"I mean, it's established pretty definitively as at least 4 1/2 billion years old," he said. "I was referring to a theological debate, and which is a pretty healthy debate.
"To the extent there is any kind of debate about the age of the Earth scientifically, I'm not in a position to mediate that," he said.
"I just think in America we should have the freedom to teach our children whatever it is we believe," he said. "And that means teaching them science. They have to know the science but also parents have the right to teach them the theology and to reconcile those two things as they believe and see fit."