Mars And The Living Desert Problem

I keep thinking back on the Mars mission special I watched a week ago. A space probe professor type made a remark that, to the great disappointment of all the space probe professors, Mars looked like the Sonoran desert or something. Well, not actually. the 1953 Disney film The Living Desert simply contradicts that characterization. The Sonoran desert doesn't look much like Mars at all.

What appears to be the conventional wisdom promoted in the current media discussion of life on Mars is that, given liquid water and t amount of time, life will appear in some microbial form and evolve from there. The quantity given for t is at most a billion years, because that's the time span Mars is supposed to have had liquid water. Where they got that isn't explained, but let's grant it.

I went to Wikipedia's timeline of life on Earth. I recognize that all these estimates, a billion years for water on Mars, 4.4 billion years ago for the first liquid water on Earth and so forth, are subject to all sorts of challenge, but we're dealing with conventional consensus here, so these numbers will work for our purpose.

Wikipedia indeed says the first liquid water appeared on earth about 4.4 billion years ago. Then it gives a range of 3.9 to 2.5 billion years ago as the dates when the first living cells emerged. So taking the most optimistic estimates in these ranges, from 4.4 to 3.9 billion years ago was what it took for any sort of cell to result from radiation bombardments and such -- half a billion years. Of course, it could have been as long as 1.9 billion, so that would have been too long if Mars had liquid water for only a billion years, as they said on TV. But whatever.

But then the timeline gives 2.8 billion years ago as "Oldest evidence for microbial life on land in the form of organic matter-rich paleosols, ephemeral ponds and alluvial sequences, some of them bearing microfossils." In other words, this is the primordial soup of popular imagination. But in that case, t, the time value for how long it took for microbes that could leave fossil evidence to emerge from plain liquid water, is 1.6 billion years, which is longer than Mars is supposed to have had liquid water.

But these numbers apply to Earth, not Mars. Mars is colder and has less atmosphere. How this affects the equations in which t is a factor we have no idea, but the fact is that over almost 200 years of evolutionary science, nobody has come close to developing an equation that quantifies or predicts what the value tor t is in water * t = life. Nor even DNA * t = beneficial mutation.

I think it goes without saying that nobody at McDonald's would suggest a multibillion-dollar investment in a project where a bunch of professors went looking for a random formula that would generate a new secret sauce in, oh, a billion years. But this is the sort of wild speculation that's caused generations of consensus among policymakers that we send successive probes and rovers at enomous national treasure looking for something for which there is likely no fossil evidence even if it happened.

I don't know what would happen to me as a freshman in college geology class if I raised quesitons like this. If I were lucky, the prof would think I showed promise but needed discipline, and he wasn't going to destroy my career just for youthful aberration. But I might not be lucky. Bluto, after all, didn't go to class. That might be why he turned out OK.

If you want more of something, you fund it. We keep geting more of this stuff.