How Clergymen Unwittingly Helped Pave the Way for Evolution

Two men who greatly influenced Charles Darwin during his lifetime were clergymen who were also scientists. This is despite the fact that both men were anti-evolutionists. These were his life-time friend, the Rev. John Henslow, Professor of Botany, and the Rev. Adam Sedgwick, Professor of Geology, both of Cambridge University.

John Stevens Henslow (1796–1861)

Henslow was an academic with many interests. After graduation in 1818, he took part in geological expeditions to the Isle of Wight with Adam Sedgwick, and to the Isle of Man. In 1822, he was appointed Professor of Mineralogy at Cambridge, from which position he resigned after being appointed Professor of Botany there in 1825. Along the way, he had been ordained an Anglican clergyman in 1824.


John Stevens HenslowJohn Stevens Henslow (1796–1861)

Founder of the Cambridge University Botanic Garden, Henslow had, in 1821, begun to gather a dried plant collection of the whole British flora.1 His aim was “to analyse the limits of variation within ‘created’ species”.2 He used the limits of variation to define species, in a practice he referred to as “collation”. In this he was conforming to the view that species do not evolve, but have the capacity to vary within limits.

In his autobiography, Darwin wrote that his friendship with Henslow influenced his whole career more than any other circumstance.3 This began in 1828, when Darwin was an undergraduate and attended one of Henslow’s receptions. Thereafter he took Henslow’s five-week botany course three times—in 1829, 1830, and 1831.

Henslow organized teaching walks around the Cambridge area to supplement these lectures. Darwin spent so much time on these that the other lecturers referred to him as “the man who walks with Henslow”….

Continue Reading on