if single celled organisms evolved into multi cellular organisms, that is cellular chains, when and how did each and every cell give up the, "every cell for himself" way of life and start relying on certain cells to do certain jobs for the good of the whole?
It's called "kin selection", and its the same principle that explains why only one member of a beehive reproduces.
An organ is a colony of cells, and because the cells are clones of each other, there's no difference (for instance) between each of 100 cells reproducing once, and one of those cells reproducing 100 times. Or more.
So there's a survival/reproductive benefit if a colony of cells can ensure more offspring by specializing, then by all working to reproduce themselves.
So HOW and WHEN did, according to evolution, cells abandon the "every cell for himself" doctrine and start the "all for one, and one for all" doctrine? (if you get my point)
I don't know when, but I know how - because there was survival benefit in doing so.
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