erent Thomas Burnet suggested that the condition of the earth could best be explained by reference to
ordinary, slow-acting, non-catastrophic natural processes or erosion by ice, wind and water. Robert Hook
made a conclusion (based on fossils) that animals became extinct due to changes in the environment, but
just like Burnet he believed that Earth was young. In 1749, George Buffon published the theory of uni-
formitarianism. In 1788, James Hutton suggested that earth is at least hundred of thousands of years old.
Carles Lyell said “the present is key to the past”.
In 1758, Carolus Linnaeus developed system of classification - a taxonomy. Jean-Baptiste Lamarck rec-
ognized that organisms and the environment have a relationship - plants and animals are adaptive to their
environment. However, he assumed that as animals evolve, they become more perfect and complex. He
also proposed the idea of inheritance of acquired characteristics. Lamarck supposed that organisms can
develop traits by will and pass them on to offspring.
Considering this incorrect, Charles Darwin and Alfred Wallace published the theory of natural selection.
In natural selection, organisms undergo changes due to changes in the envi-
ronment, however, due to variation in species, nature “selects” the individu-
als who will survive and pass on their genes to offspring. As the individuals
produce offspring with specific traits, the traits increase in frequency in the
species and the less adaptive traits decrease in number. Note, evolution has no direction and organisms
do not evolve into more complex forms. Sometimes there is no existing variation available that will al-
low for survival, thus species become extinct.
At the time, people did not consider the evolution of humans. When others started to discover tools of
stone, some considered them “thunder stones” (natural result of lighting striking the ground). While oth-
ers believed the tools were made by people degraded from humanity. It was later accepted as a previous
February 27, 2011 5:35 PM