Reply from Adam Kuper:
Adam Kuper was kind enough to respond to the letter I recently sent him and on top of that gave me permission to post it. The response is most welcome and here it is:
Dear Dr Herbert,
Thank you for your thoughtful response. I was particularly interested since I published last year a book on cousin marriage in England in the 19th century, which has a great deal on Darwin's own interest in the topic. ("Incest and Influence", Harvard U. Press.)
Yours truly,
Adam Kuper
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