However, on the voyage, Darwin increasingly began to see evidence of life being much older.
In particular Lyell’s ‘Principles of Geology’ suggested that fossils were evidence of animals living hundreds of thousands of years ago.
He noticed that the Finch had somehow adapted to the various aspects of the particular island.
He delved further into this when he published The Decent of Man in 1871.
At the time, religion was a powerful force in society, and most people took the Bible as the infallible, literal word of God.
This included the belief that God created the world in seven days, and the world was only a few thousand years old.
He carried with him a copy of Charles Lyell’s Principals of Geology, which argued that all the features of the earth were produced by physical and biological processes through long periods of time.
Darwin saw evidence of this in the fossils he observed in the strata of rock seen on island cliffs.