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The Evolution of an Idea
• Early ideas about the origin of life were
strongly influenced by religion and philosophy
• It was thought that all forms of life have
existed, unchanged since their creation.
• Starting in the 1600s scholars began using
empirical studies (observation and
experiment) to study the natural
environment.
Carolus Linnaeus (1707-1798)
• 1735 – published Systema Naturae.
• He identified species using a standard
nomenclature.
Species  genus  genera  family  order  kingdom
• Modified slightly to became the standard way of
classifying organisms.
Georges-Louis Lecierc, Comte de
Buffon (1707-1788)
• Speculated that humans and apes have a
common ancestor.
• Suggested that as a species moved to new
habitats, the organic particles it was made up
of changed… thereby changing the species.
• Thought earth was older than 7000 yrs (which
was commonly believed).
Thomas Malthus (1766-1834)
• 1798 – An Essay on the Principle of
Population…
• Proposed populations increase geometrically,
but food production increased arithmetically
• When food ran out a struggle for existence
would follow
Georges Cuvier (1769-1832)
• Began the development of paleontology –
the study of ancient life through the
examination of fossils
• Strata (layers of rock) are characterized by a
unique group of fossil species
• Species appeared and disappeared
(extinction) over time.
• Proposed Catastrophism
– The idea that catastrophes (e.g. floods,
disease, droughts) destroy regions, allowing
for neighbouring species to repopulate
area.
Jean-Baptiste Lamarck (1744-1829)
• “Line of descent” between fossil forms and
current species.
• Organisms become more complex over time
• Proposed the inheritance of acquired
characteristics
– The idea that characteristics acquired during an
organism’s lifetime can be passed onto its offspring.
Jean-Baptiste Lamarck
Charles Lyell (1797-1875)
• Rejected Catastrophism
• Suggested
Uniformitarianism:
– Geological processes
operated at the same
rates in the past as they
do today.
– Slow and subtle change
over long periods of time
Alfred Russel Wallace (1823-1913)
• Sent Darwin his theory in 1858
• Reached conclusions that were similar to
Darwin’s at around the same time (was
working independently).
Charles Darwin (1809-1882)
• Took the HMS beagle (survey ship) in 1831
around much of the world.
• Developed the theory of evolution by natural
selection.
– Theory explaining how life has changed, and is still
changing
• Published On the Origin of Species by Means of
Natural Selection in 1860.