Darwin from Descent of Man to Emotions bring Kew under his British Museum, Darwin commented that "I used to be ashamed of hating him so much, but now I will carefully cherish my hatred & contempt to the last days of my life". In October Hooker sent sun-dews and Venus fly-traps for Darwin's experiments, then was devastated when his bedridden mother died. In his hot-house Darwin experimented, giving such plants from around the world a variety of foods and poisons, and began writing "insectivorous Plants". "The Expression of the Emotions in Man and Animals" proved very popular, selling over 5,000 copies, but an exhausted Darwin became a
The Expression of the Emotions in Man and Animals shows how human emotions link mental states with bodily movement, and are genetically determined, deriving from purposeful animal actions. He comments on the implications of the book: a single origin for the entire human species, with universal human expressions; and he stresses the social value of expression, citing the emotional communication between mother and child. This was one of the first books to be illustrated with photographs – with seven heliotype plates – and the publisher John Murray warned that this "would poke a [terrible] hole in the profits". The published book assembled illustrations rather like a Victorian family album,