Origin of Species is still one of the most controversial works of science and it is one of the most outstanding
works of science in the 19th century. The studies made by Darwin during the voyage of the HMS Beagle form a large
part of the basis for this work.
As early as 1837, Darwin's notes describe the transmutation (evolution) of species. The work on this proceeded
in private -- available for discussion with only a few close friends -- for the next twenty-two years. Darwin recognized
how controversial it would be once published.
The ideas were presented, along with the parallel concepts by Alfred Wallace, in 1958 and published as the Origin
of Species in 1859.