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The Scientists of Evolution
Most everyone knows Charles Darwin as the father of Evolution. His ideas, published in The
Origin of Species in 1858, helped establish the Theory of Evolution. He gave evidence
comparing how similar the embryology of various organisms were right after conception,
explaining that the similarities implied common early development inherited from a common
ancestor. He cited fossil evidence showing how organisms changed over time and generations
compared to their ancestral species. He compared the anatomy of different organisms and
concluded that, though different species have adapted for their own niches/environments, they
continued to display common structures that support their descent from a common ancestor.
Now, we also have biochemical evidence of amino acids and proteins in common across
different organisms that suggest how closely or loosely related organisms are.
Darwin believed in Natural Selection, or survival of the fittest. That is, traits or variations that
best allow individuals to survive and reproduce will be more likely to be passed down to future
generations. Individuals with less fit traits or genes would die out. He got this idea from
economist Thomas Malthus, who had published an essay explaining that unchecked human
population growth would outpace available food supplies, leading to competition over resources.
Darwin believed Natural Selection was not according to any plan, but was driven by
environmental changes, mutations, etc. and that those better equipped (better adapted) for
competition would be more likely to survive.
Darwin was not the only scientist to contribute to Evolution. Before Darwin published his book,
Jean-Baptiste Lamarck had some ideas of how traits were passed on from one generation to
the next. Lamarck suggested that if an organism changes during life in order to adapt to its
environment, those changes are passed on to its offspring. That is, there used to be giraffes
with short necks, but they stretched reeeeeeeally long to reach food on taller branches so now
all of their offspring have long necks. Lamarck also believed that if you did not use a
structure/body part, your descendents will eventually lose it completely. He believed all of this
was predetermined and that the results were already established.
While Darwin and Lemarck both agreed that organisms changed over time, Lemarck’s ideas
have been proven false. With the work of Gregor Mendel and the advent of the study of
Genetics, we can prove that, while some traits are passed onto offspring, not everything that an
organism does affects their children. For example, according to Lemarck, having pierced ears
would mean all of your offspring would be born with pierced ears!
