It really struck home to me that we are (in Dawkins' words) "colonies" of cells acting together...
I can imagine each cell "thinking" it is alone in the environment, simply not knowing that actually it is busily communicating with millions of other cells' products, rather than with the environment external to the body.
“The mechanism of chemical sensation that originally evolved to detect environmental substances now form the basis for chemical communication between cells and organs, using hormones and neurotransmitters.”Anyone else find this oddly inspiring and awesome? So simple... there wasn't two different paths of evolution for cellular senses, but one... which became used in two very different circumstances!
"Neuroscience" by Bear, Connors and Paradiso, p189</p>
I guess that is why some diseases which are basically single-cell sometimes react en masse or change their behaviour en masse. (We have found that sometimes a critical mass of a certain excreted chemical causes a group change in single-cell disease behaviour).
I've added some of this to "The Evolution of Life from the Primordial Soup to the Cell" by Vexen Crabtree (1999) - the page really does need to be made scientific, rather than rambling!