I see them as being terraformers and probably an ampule held the primordial soup that was within the water that developed on our planet when its atmosphere began to settle down.
People tend to not realise for a fair time the Earth was a barren rock without an atmosphere even, it is thanks to its gravity that (put very simply) it managed to pull in enough ice clusters from space and it was at the right heat to get build-ups of water, which led to an atmosphere being created.
Be interesting to see what the Jockey(s) will do. If they filmed at a waterfall, I assume they somehow get our waterworks going, which will of course hold all the genetic material that the plants and animals will evolve from.