Regarding This planet ...
From "Darwin's Ghost" by Steve Jones, page 284.
"About a thousand genes are shared by every organism, however simple or complicated."
Bricks are used to build walls, roads, houses, fireplaces, etc,
because they are a good thing to build those things with,
but it doesn’t mean they all “descended” from a common ancestor.
However, looking inside the cell, the complexity precludes accidental, gradual development.
By the way, I do believe we descended from a common ancestor.
His name was Adam.
Which shows that life is a continuum, a theory known to the ancient Greeks.