When and how did the process of cellular respiration first begin? Seeing as the first thing which it needs is two molecules of adenosine triphosphate, its end product, to break the glucose in pyruvate, it's a sort of chicken and egg question. Is there currently any research concerning this? Have scientists been able to draw any conclusions yet?

I'd love to give you the paper on the evolution of glycolysis, but ScienceDirect is having none of it right now. If you can get to it, it's in Progress in Biophysics and Molecular Biology, authors Fothergill-Gilmore and Michaels.

I did find it online, but it isn't available for free download. If you've read it, could you summarise it for me?