> Before Darwin died, he announced that his theory was made up, and
> false.

 You have fallen for a myth which is popular among fundamentalists
 and frequently related by preachers or in tracts.  This one is
 catalogued in an article by the cultural anthropologist Tom McIver:
 "Ancient Tales and Space-Age Myths of Creationist Evangelism (_The
 Skeptical Inquirer_, v10 n3 [Spring 1986]).

 The source for this tale is a mysterious "Lady Hope", who claimed
 that she had visited Darwin on his deathbed, heard his confession
 (he had never intended his theory to be taken as seriously as it
 was, and was sorry for the evil influence of the false doctrine),
 and then joined Darwin in bible reading and hymn singing.

 The earliest source for this story usually cited by creationists is
 an article in the _Bombay (India) Guardian_ of March 25, 1916.  The
 _Guardian_, however, cites as its source the _Boston Watchman
 Examiner_, which apparently asked "Lady Hope" to write up the
 account which she had given at a local educational institution
 founded by the evangelist Dwight L. Moody.

 The Lady Hope story contains a number of inconsistencies,
 erroneously placing Darwin's death in the autumn, for instance.  In
 addition it is inconsistent with all the verifiable accounts (i.e.,
 of family members who we -know- were present) of Darwin's death.
 Also, Darwin's theory was not, as the myth states, an idle
 speculation of his youth, but developed painstakingly over many
 years.  Furthermore, we know that Darwin was extremely anxious that
 his theory should be taken seriously, and in fact delayed its
 publication twenty years due to anxiety about its reception.

 For these and other reasons this story of Darwin's deathbed
 conversion has been debunked even by a number of fundamentalists.
 (McIver gives the references.)  I also note that, in a manner
 typical to the retelling of popular legends, you exaggerate on the
 original tale, saying that Darwin "announced" (as though publicly)
 that his theory was false, while the standard legend claims only a
 private confession to one individual.