"Many biologists define life as anything that undergoes Darwinian evolution.
--We pretend that makes sense, but if you look it makes no sense at all.
Q: What is the unit of Darwinian evolution?
Q: Is it the gene?
Q: Is it the cell?
Q: Is it a multicellular organism?
Q: Is a city evolving?
Q: How about Gaia?
Q: Is that a life form?"
Charles Lineweaver, New Scientist
Charles Lineweaver, New Scientist