1. the science part of the series is just tagged along and is not comprehensive in any way shape or form.
2. zero cohesion, as it feels the evolutionary points discussed here were just selected based on the points they were able to gather rather than the actual natural path a planet would take.
3. the actual visuals from the said "Alien Worlds" i.e. the cgi part is merely 10% of the whole series.
If you expect to learn some non related cool facts about evolution the way it happens on earth and how it happens on earth, sure this series is for you, but don't go in expecting to see how a unique world different than ours would function because there is just a sliver of that here.