I WONDER - Why Were The Galapagos Islands Important To Charles Darwin?

The Galapagos Islands are renowned for Charles Darwin's visit in 1835 during his voyage on the HMS Beagle. His observations of the islands' unique flora and fauna, and the variations among species on different islands, were crucial in developing his theory of evolution by natural selection. Darwin's seminal book, 'On the Origin of Species,' published in 1859, is a cornerstone of scientific literature.

What unique features of the Galapagos Islands did Darwin observe?

In what year was 'On the Origin of Species' published?