Haeckel was most certainly not a card-carrying atheist. Here, for instance, is Haeckel in denial mode: “The charge of atheism which still continues to be levelled against our pantheism, and against the monism which lies at its root, no longer finds a response among the really educated classes of the present day.” And again, in the same book, “…I conclude my monistic Confession of Faith with the words: ‘May God, the Spirit of the Good, the Beautiful, and the True, be with us.’”

While I have no direct quotes of Haeckel relating to his eugenic views, it is notable that everyone who quotes him on the subject says much the same thing: he was a racist who believed in implementing eugenic policies. If you have access to original sources that prove otherwise, I would be pleased to see them. In the meantime, I trust you will forgive me for siding with the near-universal opinion of other writers.

I’d like to close by pointing out that the original post made it clear that horizontal gene transfer was more important in single-celled creatures, a fact you seem to ignore. You also seem to be unaware that horizontal gene transfer is still a factor in vertebrate evolution, if not as important. Around 8% of the human genome is made up of viral gene fragments, and although technically not horizontal transfer nearly 50% of our genome is made up of LINEs.