As I said before, Lyell thought that the earth was very old. I think he suggested a possible age in excess of 100,000 years. That was useful for people like Darwin and Huxley who needed more time then the Bible seemed to give for their natural creation mythology to work. That was until genetics got involved in dispelling the “combined trait” fallacy.

Genetic traits don’t tend to combine to produce new traits. They work more in a either-or fashion. But there was a weird genetic variable that could be enlisted to keep the “evolution” story alive. That was the, “mutation”. Mutations are responsible for something like, 4000 different human diseases. They tend to occur at certain places in a genome and not everywhere and they are generally lethal, or certainly non-beneficial to the host organism.

That problem can be overlooked more readily if you plug in more time into the equation. So, since Lyell there has been a rather dramatic increase in timescales for life on this planet. The crushing blow dealt to Darwin’s natural creationism story from genetics has been glossed over with more time. A lot more time in fact, from Lyell’s 100,000 years to the present 5,000,000,000 or so. I guess time is an easy thing to fudge when you need to.