Imagine you could ask Slartibartfast (look him up!) any question about the Earth. What would you ask him, and why?
This prompt was a bit of a leftfield task for my students. Many of them have never read/listened to/watched The Hitchhiker's Guide to the Galaxy. I, on the other hand, apparently made my entrance into this world while my father repeatedly read the first chapter of the book out loud, and the radio series was the soundtrack to many long car journeys.
When I got to Cambridge University, it turned out that one of my lecturers, Simon Conway Morris, was rather a big fan of the book too. His lecture notes were peppered with references to 42, "life, the universe and everything", and in particular the character Slartibartfast. Slartibartfast designed planets - he designed Earth, and after the Vogons blew up Earth #1, he was in the process of designing Earth #2. This prompt is a paraphrase of a genuine Part III long essay exam question we sat. Buggered if I can remember what I asked him - it was a decade ago - but this is what I'd ask this time.
When you make a new planet, do you have to start life off from scratch, or can you copy and paste it in from another planet?
I've already mentioned in the previous post my interest in abiogenesis. If life arises independently on each planet, then the conditions must have been optimum for the synthesis of more complex organic molecules on the Earth at the time. If it is possible for organisms or complex organics to be transported through space, then the conditions under which life originated could be very different to those experienced during Earth history. The hypothesis that living organisms had extraterrestrial origins (and we're talking single-celled organisms or even nucleic acids here, not ET phoning home) is called Panspermia - most of my students will only have heard of it in the context of the film "Prometheus" - the film is not a scientific account of this hypothesis...
What made you decide to go for carbon, hydrogen, nitrogen and oxygen as such fundamental elements? Why not silicon, lithium, boron and fluorine?
Life as we know it requires water. All metabolic reactions occur in an aqueous environment, and I should think (though I am not a great biochemist) that such a demand places certain constraints on the molecules involved in these reactions. But I'd be interested to know if this is the only option. I remember the odd "Star Trek" episode involving silicon-based life-forms - no jokes about Katie Price, these were invariably sentient rocks (oh okay then, you can make a joke about Katie Price).
Seriously, what was wrong with dinosaurs? Why did you kill them off and leave their bones in the ground as tantalising glimpses of our prehistory?
Just because, damnit, I think they're awesome. I'd like to understand exactly what was going on environmentally at the end of the Cretaceous, and to be able to see why non-avian dinosaurs and many other taxa were unable to cope with these conditions. Palaeontologists have a jolly good idea about this, but it would be nice to understand what made dinosaurs so successful, and why they could not weather the bolide impact.