On this date, the American biochemist Sidney Walter Fox was born. In the 1960s at the University of Miami, Fox found that when he heated Stanley Miller’s amino acids (created through simulation experiments) to temperatures that would have been present on the volcanic primordial Earth, in conjunction with aspartic and glutamic acids (also created through simulation experiments), they formed protein-like polymers that he called”proteinoids”.
Fox observed that when proteinoids or “thermal proteins,” are placed in water, they self-organize into microspheres or protocells, possible precursors of the contemporary living cell. Under a microscope, the microspheres look like primitive cells. In fact, artificially fossilized microspheres are indistinguishable from the earliest known microfossils that date back to about 3.5 BYA. Fox argued that RNA or DNA need not date back to the origin of life, and he showed that proteinoid microspheres exhibit growth, metabolism, reproduction (by budding), and responsiveness to stimuli – all properties of life – though without a genetic system. Although hesitant to claim that these were alive, Fox stated that they were undeniably “protoalive”. This is not an evasive answer. As Tim M. Berra says in Evolution and the Myth of Creationism (1990):
For centuries, science knew nothing intermediate between non-living and living things, but today the distinction is not at all clear. Since life evolved from non-living matter, at some point we must arbitrarily draw a line and say that everything beyond that point is alive. Viruses, for example, appear to be alive when they infect a host, but seem to be non-living when outside a host.
As a result of his monumental discovery of thermal proteins and their self-organization into protocells and that these protocells exhibit virtually all of the properties associated with life, Sidney Fox was invited to lecture widely throughout the world. Even Pope John Paul II and his advisers, on at least three separate occasions, invited Fox to the Vatican to explain his work on the synthesis of cellular life in a test tube.