8.Again this relationship is valid not only for birds, but also, similarly on average within the systematic unit, for all other organisms (plants, animals, unicellular organisms).
9.If that's true, though, then there's a problem: Most unicellular life at the time was photosynthetic -- like cyanobacteria and phytoplankton – and they need light to live.
10.In the 1940s, author Jack Williamson coined the term, " terraforming." To terraform is to create an ecosystem that supports living organisms—from large, complicated vertebrates, to simple, unicellular bacteria.
11.For 2 billion years, all organisms on Earth are unicellular, and they likely lived in the oceans, shielded from the hard ultraviolet light of the sun but then something remarkable happened, Photosynthesis.
12.A further argument against the simple wear and tear theory is the observation that the time within which organisms age lies between a few days (even a few hours for unicellular organisms) and several thousand years, as with mammoth trees.