Thank you both. First, this is not a thesis question, but rather one to stimulate thinking and in a small way related to a project, not one that needs more than opinion. I did the graduate student thing. This question is more for fun and thought stimulation than knowledge.
There must be dozens of Internet sources speculating life expectancy of a child born today, either limiting it to industrialized nations, less technically advanced nations or both. Personally, when I refer to child, I refer to all children, for we are a human species and not a bunch of housewives and househusbands from Orange County. As for "third world nations," I do not care for the term. In 1895, there was no third world, as the term's origin relates to post WW2 Allies and Communists, with the third world relating to everyone else. Narcistic, I think.
The environment does play in. If we keep destroying the ozone, none of us will see another century or possibly decade. If you buy in on 12-21-12, we won't make it past Macy's lay-away schedule. Overpopulation also plays in, as we have a lot more people on the planet than in 1895. The world is changing as I write this sentence. Everything is a factor.
Medicine is a Pandora's Box. Yes, we are curing diseases we caused. But we can transplant pigs valves into cardiac patients who would have died 25 years ago. It's true that we fed them the cholestrol that made them need the valve. About 150 years ago, they worked themselves to death. Now, in an industrialized nation, we are among the laziest people who ever lived. But, we have pig valves. Instead of dying in the fields working too hard, we are living obese lives in the line at McDonalds who never seem to get my order right--but that's another topic. People are living older, healthier and usually poorer than any time in recent history. Industrialized nations enjoy this glut of these people. Among the longest-lived individuals, India and Mongolia currently host many of the oldest. Geneticists may someday cure all diseases. Or, they may cause the Death Knoll. I saw I Am Legend.
In 1895, there was a relatively known chance of live birth and of survival past infancy. I've not found the rate, but the rate exists and is known and finite. For discussion purposes, let's say there was a 95% chance of surviving past age five. There also was a finite rate of those who would live past 100 years of age. What happens tomorrow will happen. Until then, all we can do is guess. If someone can predict accurately, forget this question and tell me Saturday's Powerball numbers.
Fundamentally, my topic question is mathematics. All things withstanding, do people think there is a better chance for our 15-year-olds to live another 90 years than the 1895 child mortality rate? Nonetheless, I think it's an interesting question, more interesting--at least to me--than the Republican Front-runner in NH and Iowa.