Curiosity is at the root of most of man’s discoveries and innovations; without it, it is quite likely that we might still be hunter gatherers.

Other animal forms have quite a lot of curiosity too. Dogs, for instance, smell a stranger and bark out of normal fear. To our knowledge they have never asked probing questions like, “why do all dumb humans seem to look alike and make such funny noises?” or “why do they seem to object when I try to smell their privates to see if I recognize them?”

Curiosity is also a significant word, and it is most appropriate that it is the name of the most recent space probe machine for signs of earlier lifelike matter on Mars.

I am curious to know what earth would be like, if earth becomes, in due course, like what we find on Mars today? One of NASA’s scientific leaders, Astronaut John Grunsfeld, said recently that the most interesting questions that need to be answered are not those that we expect and hope to find, but rather those that we have no clue about at all today.

Would it be possible that all our lifelike substances would vanish completely as they appear to have on Mars, if they ever existed? That’s unlikely, but much would depend on how life on earth was extinguished. A sudden apocalypse by collision? A slow and anguishing extinction from global warming? Might there still be oceans?

One possibility might be that there would be just enough global warming — even hotter and more sustained than we have experienced this summer — which would gradually reduce human population, beginning with old people who cannot handle extended heat for too long.

What would people do? If there were enough time to adjust, huge domes could be constructed to house whole cities with powerful air conditioning. But that would be tough to pull off and tougher to sustain. And what about our love of great views?

Another possibility would be to live underwater. There would be plenty of room until the water began to evaporate. That route might buy some additional time, but if land was scorched dry, how would submerged people be able to grow and get food, even with spacesuits to be used when out of the water.

Perhaps humans would quickly become extinct and their role might be taken over by, say, lobsters. We know lobsters do not like boiling water. But we also know that they become quite fecund in warmer water and that they have love lives and complex social organizations.

So far there have been no reports that lobsters have experienced political gridlock over what to do about warmer water — quite the reverse. This year, for example, in Maine there have been so many more lobsters caught than in prior years that the old law of supply and demand has driven lobster prices down from $4 last year to almost $1 this year.

It also is not clear how long it would take lobsters to evolve enough skills to operate the Internet etc. In fact there probably would not be enough time left for any form of life on earth to enable lobsters, or, for that matter, any other fish, to get anywhere to the level of where humans are today.

So, what should all this curiosity add up to and tell us today?

Perhaps we should seek universal agreement that we only have a toe hold on earth and we had better not take it for granted and use it at random.

Perhaps we should, keeping an eye on what Curiosity learns on Mars, start some serious contingency planning, which could begin with listening to scientists about global warming.

Perhaps we should ask ourselves, if we had been Martians, where and how we would have buried the vestiges of our existence, so that our manmade Curiosity might have a better chance of finding that information so potentially vital to our future existence.

As this is an election year, we should encourage our curiosity to run rampant and ask the toughest questions we can imagine of this year’s presidential candidates about their views of the future of humanity.

The choice now is not just about jobs and debt. It really is about the course of human survival!

And, that is what our curiosity should be directed towards. For a long time to come the connections among all the elements of modern society and their impact on life on this planet need even more resources than the cost of the expedition to Mars.