Abiogenesis and Dr. James Tour

This is the final video in a course on abiogenesis by Dr. James Tour. If the subject of the naturalistic origin of life from nonlife intrigues you, it may be good to keep in mind how unlikely something like that actually is. And yet here we are. How did we get here? If you don’t like Genesis, that question is not easy to answer and so far it has not been answered.

Regardless what you might hear in the media or the hype from origins of life researchers, no one has been able to create life from nonlife in a laboratory. They have done many amazing things with already existing life, but they have not started with nonliving chemicals and produced life. There are many reasons why this problem is difficult.

• Life requires homochirality. Molecules do not naturally separate into left and right handed versions, but biological molecules have to for a cell to function without overheating.
• Carbohydrates are the hardest to synthesize in a modern lab. How they could have synthesized in a prebiotic environment without lab equipment or trained technicians running that equipment is a mystery.
• Peptides are also difficult to synthesize. Any partial success in the lab involves processes unavailable in a prebiotic environment.
• Nucleotides may be easier until one tries to link them together, because they depend on synthesizing carbohydrates to get the ribose that joins them.
• Lipids are sometimes said to form spontaneously. Tour said that “spontaneously” is an origin of life researcher’s code word for “I have no idea how that happened”.
• Chiral-induced spin selectivity requires homochirality. It permits cell functions without overheating while maintaining the purity of the cell’s components.
• RNA can not replicate enough of itself to be useful. Linking parts of it together leads to errors which make it useless. It is also unstable. The RNA World hypothesis that relies on RNA alone cannot even get started.
• Life requires a non-random DNA code that can usefully direct the cell’s functions. Not just any random code will do. So even if you get past the other problems of synthesizing a cell from chemicals, the information problem blocks the process. How does mindless nature know what a useful code sequence could be?
• Life is highly ordered with low entropy and high energy. How does nature produce life without violating the laws of thermodynamics?

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While writing this essay this morning I listened to one of Greg Bahnsen’s audio lectures, Amoebas, Apes and Adam that SlimJim referenced in his post Free Bahnsen Lectures: Getting Down and Dirty.

Even though Bahnsen’s lecture is some decades older than Tour’s course, Bahnsen’s chemical arguments against life coming from nonlife is in line with what Tour had to say. And Tour’s objections to abiogenesis reinforced Bahnsen’s assessment of evolution in general, not just abiogenesis, as a “grand fairy tale for adults”.