 An aspect of reproducers sensu lato that has fascinated some is that it does not imply a particular level of reproduction or progeneration; indeed, Szathmáry and Maynard Smith consider that the major transitions of evolution each involve an evolved mode of progeneration that is more inclusive or novel than what it evolved from (Maynard Smith &amp; Szathmáry 1995; Szathmáry &amp; Maynard Smith 1997).