In his own day, Haeckel was a hugely controversial figure and a hate-figure for many Christians because of his relentless harrying of their beliefs. Historians have savaged Haeckel's reputation and Richards accepts that he was “a man of contradictions”, a driven character and a divisive figure.

But Richards succeeds brilliantly in re-establishing Haeckel as a significant scientist and a major player in the history of evolutionary thought. Richards is particularly good at tracing the origins of Haeckel’s “Romantic evolutionism”. As the author of an earlier and equally impressive study of how Romanticism shaped biological thought in the first half of nineteenth century, The Romantic Conception of Life (2002), Richards is ideally qualified for this task.

Before World War I, more people learned about evolutionary theory from Haeckel than any other source, including Darwin’s own writings. In The Descent of Man, Darwin himself praised one of Haeckel’s books, saying “if this work had appeared before my essay had been written, I should probably never have completed it.” Richards portrays Haeckel as an unjustly forgotten genius, a figure of “startling creativity, tireless industry, and deep artistic talent”. Richards argues that Haeckel was Darwin’s “authentic intellectual heir”.

You can read my review in this week's TLS (25 July), or read a longer version here.