Just watched this. I found what he said at 47:07, 48:21, and 49:42 particularly interesting. I can understand why he thinks there’s something to the alkaline hydrothermal vent hypothesis with results like that.
Also interesting to learn at 45:53 that they had a problem with their glovebox, which actually wasn’t entirely anoxic (it still had ~5 ppm oxygen because it had a defect so it was leaky), which apparently completely ruined a lot of their experiments so for a while they didn’t know why they got negative results. Once that problem was fixed, other issues they thought plagued their experiments turned out not to be an issue after all (such as the pressure of hydrogen). Just one of those practical things about research that makes it take longer than you think.
Yes, been a fan of Nick Lane on the origins of life for many years now. My opinion is that the energetic flux of life is linked to the proton (or pH) gradients, such that I don’t see any feasible way for life to have come about without an environment that provides such conditions. Additionally, you also need to have redox disequilibrium, particularly between CO2 and H2 which makes the synthesis of biomass energetically favorable. Although this reaction is difficult due to the stability of H2 and CO2, there is a kinetic barrier that needs to be overcome, this can either happen by adding energy to overcome the barrier but then the reaction is not energetically favorable (more energy goes in than comes out). Another way to do this is lowering the barrier, which is exactly what a pH gradient does, making it easier for H2 to transfer its electrons onto CO2. This transfer also happens more readily in the presence of catalyst, such as minerals containing iron, sulfer and nickel. In fact, even though life makes proteins that perform catalysis, the enzymes responsible for electron transfer and reduction of CO2 using H2 as the e-donor uses exactly these types of metal-centers. I remember Eric Smith (another person researching the origins of life) making the remark (paraphrasing) that “This seems that life has inherited geochemistry which was later enfolding it into a control system based on proteins”
The conditions present in Alkaline vents are a very close match, which makes them a very likely setting for life’s origins (of course, I am very open on hearing any other environments that provide the same or better circumstances).
Here is a good image that summarizes this hypothesis, although most of details aren’t shown of course and these are still being discussed even among those who favor the alkaline vent hypothesis.
One last thing I wished to call attention to is how eubacteria (aka bacteria) and archaebacteria (aka archaea) independently escaped the vent world. This is one detail about life that is explained by this hypothesis. Bacteria and Archaea are very similar in my aspect, but they differ remarkably regarding their membrane biochemistry, seemingly suggesting that membranes evolved independently. This was a puzzle about LUCA. What membrane did it have? If for example it had the bacterial membrane, then why did archaea replaced it or vice versa? If we assume that LUCA didn’t have a membrane, then how could it survive? An explanation provided by the alkaline vent hypothesis is that the vent compartments provided the scaffold, which was later taken over by membranes independently that allowed life to store energy from redox chemistry in the form of a proton gradient autonomously outside the vents.
Having watched the lecture now. It is good (of course!) but it does re-hash bits and pieces of things he describes in far more detail in other videos. You can watch those on his Channel on YouTube.
I’ve watched most of his videos, and have detailed notes since I teach evolution and wanted to learn more about this stuff.