Although scientists expected to find transitional intermediates, or a series of gradual steps, between what is living and what is not, Denton observed that the existence of a definite discontinuity was “finally established after the revolutionary discoveries of molecular biology in the early 1950s. ”
Ehkki teadlased lootsid leida elusa ja eluta vahelised üleminekuetapid ehk rea arenguastmeid, „leidis pärast revolutsioonilisi avastusi molekulaarbioloogia vallas 1950 - ndate algul lõpuks tõestust ” kindla eraldatuse olemasolu, täheldab Denton.