> As Marshak alludes, finding out what happened during, and led to, the missing billion years is no trivial matter. There are two reasons for this. The first is

> As Marshak alludes, finding out what happened during, and led to, the missing billion years is no trivial matter. There are two reasons for this. The first is that it just so happens to have occurred immediately before another inexplicable event – the sudden proliferation in the diversity of life on Earth 541 million years ago.