Dedicated to the teaching of Earth Sciences


Prof. Sean Tvelia Suffolk County Community College


Evolution: The Origin of Species

Evolution can be defined as the gradual development of anything overtime from a simple to a more complex form; whether it be technology, language, society, or life. Biologic evolution refers to how this process proceeds in living organisms through inheritance and natural process since the time life originated on Earth. As a scientific theory Evolution explains the historical course of biology as seen within the fossil record and is the basic for modern biology.

Although the theory of evolution is most often attributed to Charles Darwin, others, including ancient greek philosophers and western theologians have also tried to explain biologic changes observed in the fossil record. Nevertheless, for most western societies the book of Genesis and the creation story was the final word on the origin of life well into the 1700's. However as the intellectual climate changed the authority of the church was diminished, scientists began to uncover more evidence that could not be reconciled with literal interpretations of biblical scripture. Eventually scientists would come to accept the principle of uniformitarianism and it's implication for the age of the Earth. Subsequent observations by renown paleontologist Georges Cuvier also showed that many plants and animals had become extinct over time lead scientist to gradually accept the fact that individual species could change over time. Unfortunately there was no acceptable explanation for these observations.

Chapter Contents:

7.0: Evolution: The Origin of Species

7.1: Early Explanations for Evolution: Jean-Baptiste de Lamarck

7.2: Charles Darwin: The Theory of Natural Selection

7.3: Gregor Mendel and the birth of Modern Genetics

7.4: Modern Evolution

7.5: Speciation and the Rate of Evolution

7.6: Styles of Evolution