[1] https://en.wikipedia.org/wiki/Decline_of_Christianity_in_the...
[1] https://en.wikipedia.org/wiki/Decline_of_Christianity_in_the...
My question was: of the group of people who believe in heaven and also want indefinite life on earth, how do they reconcile those two ideas? The article has no bearing on that. Even if there was one person who believed in heaven, if they also wanted unlimited life on earth, I'd be interested to hear why they believe both.
As to why, a thousand years ago you didn't really have a strong counterthesis to the Intelligent Design thesis. As the Evolutionary principles became better understood and more accepted, religions have had to shift their position a bit (initially the Earth was the center of the universe, etc).
Long story short, even if people do believe in heaven, they wouldn't mind having a small hedge, just in case.