charles_darwin

30
CHARLES DARWIN AND THE ORIGIN OF SPECIES
of infection by the protozoan Trypanosoma cruzi, which the Benchuca
frequently carries, manifest some of the symptoms Darwin had. 37 In
1903, George M. Gould, a doctor, even suggested Darwin’s illnesses
were caused by eye strain. 38
Whatever the cause of Darwin’s illnesses, the important fact is
that they prevented him from working. Darwin’s literary output is
impressive. It is even more impressive when put in the context of
his frequent bouts of sickness.
Darwin continued to work hard despite his poor health. In
1846, after he finished editing the volumes on the geology and zoology
of the Beagle, Darwin began writing about barnacles (Cirripedia).
After eight years of research, Darwin published two large
books on living barnacles and two small books on extinct barnacles.
By 1855, Darwin was a world authority on barnacles. His research
on the Cirripedia also helped him with his musings about another
problem in biology: the relationship between species.
The Birth of The Origin of Species
‘‘From September 1854 I devoted my whole time to arranging
my huge pile of notes, to observing, and to experimenting in relation
to the transmutation of species.’’ This is one of the most auspicious
statements in Darwin’s autobiography. Darwin did not need to write
The Origin of Species to establish his credentials as a naturalist or to
become famous: he had already done both. His travelogue on the
voyage of the Beagle was a best seller. His volumes on the geology
and zoology of the voyage of the Beagle were highly praised and valued
by scientists around the world. He had done pioneering research
on the origins and structure of coral reefs. He was the world expert
on barnacles. In 1853, he was awarded the Royal Medal by the Royal
Society in recognition of the work he had done: the medal was one
of the highest awards a scientist could receive. His father would have
been proud. No one could call Darwin a wastrel now.
However, even while he was working hard on his other projects,
Darwin was musing over some of the phenomena he had seen,
particularly in South America: the fossils he had discovered, the geographical
distribution of closely related animals, and the slight differences
between species on each island of the Galapagos. What was
the significance of these facts? The facts ‘‘could only be explained on
the supposition that species gradually became modified,’’ thought
Darwin. ‘‘The subject haunted me,’’ he wrote. 39 His explanation ran
counter to established scientific thinking, but Darwin did not drop