Great Geologists | 55
Ctenoid fish fossil, from Louis Agassiz, Recherches sur les poissons fossiles, 1833–43.
T.C. Chamberlin were actively attempting to map the extent of
the North American Pleistocene ice sheet. They also recognised,
as Agassiz had suggested, that there was more than one period
of ice sheet expansion. In short, Agassiz had instigated the
science of glaciology and study of glacial phenomena in the
geological record.
For much of the early part of the 1840s, Agassiz was involved
in compiling his Nomenclator Zoologicus, a classified list, with
references, of all generic names and those of higher taxonomic
groups employed in zoology. By 1846, he was ready for a new
challenge and aided by a grant from the King of Prussia, Agassiz
crossed the Atlantic with the twin purposes of investigating
the natural history and geology of North America and delivering
a series of lectures on “The Plan of Creation as shown in the
Animal Kingdom”. Like Buckland and many other geologists of
that time, Agassiz endeavored to square religious teachings with
his observations, a trait that would ultimately lead him to take an
anti-evolutionary stance.
Society in Boston welcomed this charismatic visitor with open
arms and he was soon persuaded to stay, the city and Harvard
University becoming his home and scientific base for the rest
of his life. He was a gifted teacher, emphasising the study of
specimens and outcrops over book-learnt knowledge, and many
of his students became notable scientists in their own right.
He continued his studies into past glaciations and recognised
the sediments of a glacial lake that was a precursor to modern-
day Lake Winnipeg (subsequently named Lake Agassiz in his
honour). As is demonstrated by the numerous geographic
locations and fossil and living taxa named in his honour, Agassiz
was arguably one of the best known natural historians in the
world in the 1850s. A celebrity scientist in modern terms.
Troubled by ill health, he still took part in two notable
expeditions, one to Brazil from April 1865 to August 1866 and
a further expedition to South America, travelling through the
Magellan Straits in 1872. These trips had many objectives, but
one key strand was to gather evidence to refute the tenants
of evolution, as laid out by Charles Darwin in On the Origin of
Species, published in 1859. The idea of the “transmutation
of species” was an anathema to Agassiz. In his view, every
species was created by design — “a thought of God” — and
God had provided different environments through time, in
which successive groups of species could flourish before being
replaced with a more advanced set. This was creationism meets
catastrophism.
Ironically, Agassiz gathered evidence that was used to support
evolution. He noted that within a particular taxonomic group,