 This extension of Queller and Strassmann’s view of individuality may prove useful in fleshing out more details of what Godfrey-Smith (borrowing a term of Huxley’s) calls the movement of individuality (2013: 33). This refers to the ways in which new kinds of individual evolve slowly, over geological time scales, from recurring collaborations between different types of Darwinian individuals. Such partnerships sometimes lead to new examples of paradigm individuals, but other times falter or stall at the mere collaboration stage with no new individuals at all. Closure of a pathway to a higher degree of individuality could be brought about by either a drop in the internal ratio (reduced individuality because of internal matters) or a rise in the external ratio (reduced individuality because of external matters).