Abstract

The origin of life is one of the biggest questions in science. Strangely, for more than half a century, the question has been limited largely to a question in synthetic chemistry: how can the ‘building blocks of life’, especially the amino acids and nucleotides that comprise proteins, RNA , and DNA , be synthesized under ‘plausible prebiotic conditions. Most of these precursors have been successfully synthesized, but starting from reactive molecules such as cyanide and cyanamide, and typically energized by UV radiation. This has led to a new problem, which is that prebiotic chemistry does not link up well with biochemistry as we know it, which tends to use H2 and CO2 . Recent years have seen a radical shift in perspective, with coherent new ideas emerging from phylogenomics, microbiology, astrobiology, cosmology, geochemistry, and electrochemistry. I shall give an overview of recent work which suggests that life may have started in deep-sea alkaline hydrothermal vents. These systems provide labyrinths of interconnected cell-like pores, with structures that support steep gradients similar to those found in modern cells, potentially driving the growth and replication of simple protocells. I will finish with some ideas on how the genetic code might have arisen in this setting.