The History of Life Biological Evolution

Uniformitarianism Hutton and Lyell believes “the present is the key to the past” assumes that the natural processes governing the earth today operated at the same rate throughout history

Uniformitarianism problems catastrophes creation with apparent age

Jean Lamarck theory of need theory of use and disuse theory of inheritance of acquired characteristics basic problem: passing on acquired characteristics to future generations

Charles Darwin On the Origin of Species by Means of Natural Selection (1859)

Darwin’s Theory descent with modification theory of natural selection common ancestor theory of natural selection artificial selection natural selection survival of the fittest

Darwin’s Theory problems Natural selection regroups existing characteristics. No new genetic information is created.

Charles Darwin On the Origin of Species by Means of Natural Selection (1859) The Descent of Man (1871)

Geologic Column the sequence of fossil-containing rock layers that shows the supposed rate of evolution

Dating Methods also use the principles of uniformitarianism radiometric dating methods measure the decay of a radioactive substance into a nonradioactive substance

Hugo de Vries Species and Varieties: Their Origin by Mutation used the term “mutations”

Neo-Darwinism mutation-selection theory blends Darwin’s theory of natural selection and de Vries’s theory of mutations

Mutations & Evolution Mutations are random. Mutations must occur in reproductive cells. Evolution requires “good mutations.” happening repeatedly in many, many organisms

Mutations & Evolution Too many mutations will kill an organism. genetic load

Punctuated Equilibrium During some periods of time, evolution occurred rapidly, while at other times, very little evolution took place.

Homologous Structures organs that are similar in structure and function in two different organisms

evolution of a similar structure in unrelated species Convergent Evolution evolution of a similar structure in unrelated species

organs which no longer have any function Vestigial Structures organs which no longer have any function