Tuesday, 3 September 2013
Life From Mars?
Two prominent scientists has come out and stated that life would have more likely developed with the conditions on Mars four billion years ago, rather than Earth. They both forward that old conjecture, that life started on Mars and was seeded to Earth (panspermia is the term, work that very carefully into workplace conversations).
One chemist postulates that for RNA to develop a certain environmental concentrations of elements such as molybdenum, boron and oxygen needed to be at a certain level which was happening on Mars at that time, but not on Earth. RNA plays a role in coding, regulation and expression of genes and is believed to predate DNA in development. It is believed that very early life was governed by RNA reactions.
While the scientist puts forward a good argument that conditions were ripe on Mars at that time for life to spring forth, I think it is a large jump to assume that life could not also independently arise on Earth. The panspermia argument seems a stretch since that means this RNA would need to survive an impact of an asteroid on the surface of Mars, transportation through the vacuum of space (huge amounts of radiation), entry into Earth's atmosphere and finally impact on the surface of Earth. Not the most likely of events.
Another scientist has stated that the large concentration of phosphates on Mars would have promoted life to flourish there. This is another great argument for life arising independently on Mars, but not panspermia.
Phosphates are chemical compounds that contain phosphorus and oxygen. They are very common in all life, with the framework of your DNA being made of phosphate chains, as well as phosphates being used to deliver energy into your cells. You can see the power of phosphates upon life when you see the runoff of agricultural phosphate fertilisers hit large water bodies. You get algal blooms. The bacteria and algae go batshit crazy for the stuff.
So even if it is a stretch to reason that Earth life was seeded from elsewhere, all this evidence for great conditions for life on Mars means that our searches may not be in vein and that some form of life probably did flourish on Mars at one time.