More about how evolution works: multicellularity (Evolution)

by David Turell , Monday, October 31, 2016, 17:10 (2943 days ago) @ dhw

dhw: ... but I have said over and over again that the two purposes “related to evolution” that are clear to me are survival and improvement.

DAVID: And I have emphasized a drive to complexity as the main force in evolution.

dhw: I regard innovations such as the senses, sexual reproduction, brains etc. as improvements. You may disagree. Of course such things involve greater complexity. However, I have no idea why your God or organisms themselves should create complexity for no reason other than complexity.

Answer, the only road to humans is increasing complexity.

DAVID: This article from MIT professors agrees:
http://www.mdpi.com/2075-1729/6/3/25/htm

QUOTE: It seems plausible that life started as a simple organism, close to this “wall” of minimum complexity. From that simple Last Common Ancestor (LCA), life can evolve genetic, morphological, developmental or behavioural complexity in one of three directions. It can become simpler, it can remain the same, or it can become more complex. If the LCA was a “minimal cell” then it cannot become simpler. However it can become more complex. Such more complex life can also evolve to become simpler or more complex. With time, the most complex life (however complexity is defined) is therefore likely to become more complex. While evolution of simpler forms from complex ones is common, and while the “average complexity” of the biosphere might be unchanged (if it is meaningful at all), the most complex organisms are likely to be more complex.

dhw: Brilliant! Should be published in an anthology of parodies.

The reasonable part is that bacteria could not devolve to anything simpler and live. They are paraphrasing Gould.