One of the biggest problems with any naturalistic explanation of life is trying to account for how it got started. The problem of the origin of life (OOL) is the gravamen of Stephen Meyer's excellent book Signature in the Cell in which he argues compellingly that no naturalistic explanation ever advanced can explain how the information it takes to run a living cell could have been produced solely by natural processes and random chance.
Jack Szostak is a prominent OOL researcher who's confident that a naturalistic answer will indeed be found eventually. He's published a paper in which he discusses six of the major problems that must be overcome by any such explanation and offers a possible way forward in the solution of each.
Chunkdz at Telic Thoughts summarizes Szostak's argument and then wraps up his summary with this biting piece of satire:
We now have a picture of how life may have developed under prebiotic conditions. One can easily envision a scenario in which the earth was bombarded by meteorites containing amino acids, organic compounds and fatty acids which had passed through the circular polarized light of an interstellar molecular cloud, then cyanamide and glycolaldehyde were mixed in a freshwater tide pool and allowed to sit overnight, glyceraldehyde was then added and allowed to incubate overnight before reacting with cyanoacetylene in another tide pool containing a buffered aqueous solution of pH 6.5, then phosphorylated with urea and ammonium salts under heat, dehydrated and rearranged via intramolecular nucleophilic substitution before being allowed to cool and rehydrate and subsequently bathe in ultraviolet light. Once all the necessary nucleotides were present they were concentrated around freshwater thermal vents covered with montmorillonite clay and metal hydride which was occasionally exposed to the air for dehydration and concentration. Once in sufficient concentrations after a few freezing cycles and subsequent grinding, chunks of montmorillonite clay were scooped into fatty bubbles where they began to polymerize in the relative safety of their protective bubble of fat. Then when the molecules started replicating and the bubbles allowed more raw materials to permeate their fatty membranes, highly charged molecules caused the bubbles to become long and skinny which made them break and form tiny "baby" bubbles which continued to grow as long as they remained in a cold pond with a local geothermal feature nearby. Then Darwinian evolution took over and facilitated the complex machinery which we find in modern cells.
Of course, there are still a few unanswered questions.
Indeed. The problem with such scenarios as Szostak envisions is not that they strike the mind as quite nearly impossible but rather that naturalists believe the fortuitous collocation of miracles they require actually happened without any input by an intelligent mind.
The difficulty is not in believing that such things happened, of course, since similar things happen every day in laboratories around the world. The difficulty is in believing that they could've happened purely by chance apart from any intentional intelligent agency. That's something that never happens in the lab.
Having rejected a priori the possibility that such an intelligent agent was involved in the OOL, the hypotheses the naturalists serve up to us are just too easy to parody, as Chunkdz's example illustrates.
RLC