New Form of Life

You heard about the NASA conference, may be you watched it and later on all the comments in the news. All the news showed disappointment,some of them found the conference a bit ridiculously. A bacterium, not a real alien!
I think, that was a very important discovery. We always assume to be the 'top invention' of the universe. So all the more or less intelligent forms of alien life has to be similar to us. See all the science fiction movies (I like them)
But this bacterium shows us that nature has different ways to build living cells. So the life here on earth is only one of millions of different ways to do that.
How often are there mistakes in growing cells. And may be after many attempt one of those 'mistakes' is the one that has a better chance to survive then the ancestors.
Are we one of those 'mistakes'? Alga and later on plants have been long before us on earth. The chlorophyll (what makes a leaf green) is there metabolism mediator. This molecule has in it's center one magnesium atom.
Plants produce oxygen. When there was enough oxygen in the atmosphere some thing happened similar to the change in that bacterium: the magnesium atom was replaced with an iron atom. The basic 'bricks' to build chlorophyll and our hemoglobin are the same. But now that basic substance for all metabolism was able to bind oxygen instead  of CO2. A much more efficient metabolism was developing.
There must be endless tries to change cells. And suddenly there is a new form to outlive the old one.
That takes millions of tries and when the environment is right, there is a success. Our life here on earth is to short to overlook failure and success of these tries. That means we are not the end of the line.