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sis. The ship made stops at Brazil, Patagonia, and the Falkland
Islands, sailed through the Straits of Magellan, and then on to
Chile. In Chile, Darwin crossed the Andes into Argentina. From
the west coast of South America, the Beagle then journeyed to
the Galapagos Islands, off the coast of Equador, and from there
across the Pacific Ocean to Tahiti, New Zealand, Australia, and
Cape Town. The Beagle docked in Plymouth in October 1836,
the ship s mission finally completed.
It would soon become apparent that the most significant
stop made by the Beagle was the Galapagos Islands. Darwin was
there for over a month in the early autumn of 1835, and among
the many specimens he collected were the different types of
finches that he found on these tiny volcanic islands. Nine
months later, the Galapagos were still on his mind; he would
write in his diary, When I see the islands in sight of each other
194 THE MAN WHO FOUND TI ME
and possessed of but a scanty stock of animals, tenanted by these
birds but slightly differing in structure and filling the same place
in nature, I must suspect they are varieties . . . if there is the
slightest foundation for these remarks, the zoology of the archi-
pelagoes will be well worth examining: for such facts would
undermine the stability of species.
Back in England, it would not take long for those tiny birds
to start a scientific revolution. Darwin thought that they were
simply different varieties of the same species; but, as he did with
all his collected specimens, he sent them to an expert for formal
analysis. John Gould (1804 1881), who was the taxidermist for
the Zoological Society, and known as one of the most careful
ornithologists in England, took on the task. In March 1837,
Gould told Darwin that the birds were not different varieties;
they were different species. The importance of this finding was
not lost on anyone; there was even a front-page article in the
London Times about it. For Darwin, Gould s news was a bomb-
shell, as significant as the day on St. Jago when he became aware
of the great age of the earth and its slow but constant changes.
Now it was clear that animals, perhaps all life, also experienced
slow but constant changes, so much so that over time, animals
that were separated from each other, as the finches on the Gala-
pagos were, became distinct species. In July of that same year,
Darwin started a new notebook with the heading The Trans-
mutation of Species.
The third and last flash of insight for Darwin s theory of
evolution occurred on September 28, 1838 (Darwin s life is so
well documented, through his careful notes and diaries, his
THE HUTTONI AN REVOLUTI ON 195
numerous letters, and his own autobiography, that we actually
have precise dates for these crucial turning points). On that day,
seeking relaxation from his intense studies, which were at fever
pitch in the several years after the Beagle returned, Darwin read
a famous work that he had never read before: Thomas Mathus s
forty-year-old Essay on the Principle of Population (1798). Dar-
win was having difficulty with the transmutation of species and
his thinking was stalled at the time because he could not devise
an engine that drove the process, much as Hutton had at first
struggled to find a mechanism for the renovation of land. Dar-
win already knew that different varieties of organisms were born
every day, and that the variations were inheritable; that is, they
were passed down to offspring (biologists would not understand
the specifics of mutations and genetics until well into the twen-
tieth century). For example, in the finch population on the Gala-
pagos, every day a newborn appeared that had a slightly longer
beak than its parents, or slightly more colorful plumage, and that
newborn would grow to be a reproducing adult whose own off-
spring would also have the longer beak or more colorful
plumage.
Mathus now provided the reason why simple variation, over
time, meant new species: overpopulation. Because there was not
enough food, shelter, and territory for every offspring of an
organism, there was competition among them for these scarce
commodities; the ones who were more able to acquire these
resources would be more likely to find a mate and reproduce
successfully than the ones who were less able. If a variation such
as a longer beak, which gives the bird the ability to find and eat
196 THE MAN WHO FOUND TI ME
seeds found deeper in crevices, helped in the quest for more
resources, it would eventually be propagated through an entire
population. And over great expanses of time, if the population
became separated from others (as happened with the finches in
the Galapagos), these small changes would lead to separate pop-
ulations that would no longer be able to reproduce with one
another: new species.
Charles Darwin sketched out his theory of evolution in a 30-
page manuscript in 1842. Then he expanded this first effort into
a 200-page essay, copies of which he gave to only a handful of his
closest friends, his scientific confidants, in 1844.
Though not one of Darwin s confidants, Charles Lyell had
become a close friend of the naturalist soon after the Beagle
landed in England in 1836. Darwin s letters from the ship to his
colleagues in England generated tremendous interest among the
science community in London, and Lyell was the current star of
that community, thanks to the impact of his book. Lyell called on
Darwin soon after the Beagle landed, and the young man was
honored to be so well regarded by a fellow scientist whose work
he admired. Their friendship remained close for the rest of their
lives, even though for many years Lyell could not bring himself
to admit that natural selection led to the creation of new species;
he finally did so in the tenth edition of Principles of Geology
(1867 1868).
Nonetheless, Lyell played an integral role in the official
debut of the theory of evolution and the publication of Darwin s
Origin of Species. On June 18, 1858, Darwin received a letter
and twenty-page paper from Alfred Russel Wallace, a young nat-
THE HUTTONI AN REVOLUTI ON 197
uralist with whom Darwin had been corresponding for several
years. Wallace was hoping that Darwin would read the paper
and then send it on to Charles Lyell to consider for publication
in the journal of the Linnean Society (Lyell was the president of
that organization). To Darwin s shock and deep dismay, the
enclosed paper was a sketch of a theory almost identical to Dar-
win s theory of evolution by natural selection. When he sent the
paper to Lyell, Darwin wrote, If Wallace had my MS sketch
written out in 1842, he could not have made a better short
abstract. Lyell and Darwin s friend, the botanist Joseph
Hooker, acting like King Solomon, together made one of the wis-
est decisions in the history of science: They decided that Wal-
lace s paper would be formally read along with one by Darwin
(based on his 1844 treatise), thus guaranteeing that the two men
would receive joint credit for the discovery. On July 1, 1858,
extracts from Darwin s and then Wallace s papers were read to
about thirty members of the Linnean Society (Darwin was not
present for the reading, his last child having died of scarlet fever
just three days before). Darwin s secret theory was finally out; he
now shared its authorship with Wallace.
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