We touched on an interesting concept here.
Self-assembly is a requirement for
any non-directed origin of life mechanism.
This means that atoms and small molecules
somehow assemble themselves into
larger molecules.
If you have a planetary surface covered with
oceans and land and just a sea of atoms,
what are the chances of self-assembly?
Many people now favor a view of life's
origin in which assembly takes place in
small, confined area. This could be a
small pond or a microscopic cavity.
This is another argument for mineral
surfaces being involved somehow.
The reason is that any interesting collection
of molecules in a small area are more likely
to run into each other than if those two
molecules were swimming in a big ocean.
You can see, though, that this argument comes
down probabilities (as does much of this
class).
Can enough Cs and Hs (and Ps -- don't
forget phosphorus!) get together enough
of the time that a series of phospholipids
can form a sphere or bi-layer?
How much water is required to make this happen?
Obviously some, otherwise the hydrophobic properties
of phospholipids don't matter. But if you have
too much, what are the odds the molecules will
find each other in the large ocean?
The list of questions goes on.