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Baylor > Department of Geosciences > About Us > FAQs about Geology > Does the fossil record support the idea of biological change over time (biological evolution)?

Does the fossil record support the idea of biological change over time (biological evolution)?

Yes. The fossil record clearly indicates

  • a progression in complexity of organisms from very simple fossil forms in the oldest rocks (>3.5 billion years old) to a broad spectrum from simple to complex forms in younger rocks,

  • that some organisms that were once common are now extinct, and

  • that the living organisms inhabiting our world today are similar (but generally not the same) as organisms represented as fossils in young sedimentary deposits, which in turn have evolutionary ancestors represented as fossils in yet older rocks.

Mammals, for example, are prevalent today and can be traced back in the fossil record for approximately 200 million years, but are not present as mammals in the fossil record before that; however, fossil forms that have reasonably been interpreted to be associated with the evolutionary precursors to mammals are found in older rocks.

Whether biological evolution occurs has not been a matter of scientific debate for more than a century. It is considered a proven fact. The specific mechanisms of biological change over time continue to be a topic of active research, and include mechanisms proposed by Charles Darwin as well as more recently developed ideas based on our growing knowledge of genetics and molecular biology. Using the methods of modern science, our knowledge of the fundamental mechanisms of life has grown enormously since the initial characterization of the role of DNA in reproduction, inheritance and evolution in the mid-1950s.

The American Geological Institute and The Paleontological Society, partnering with the most respected geoscience societies in America including the Geological Society of America, the American Geophysical Union, and the American Association of Petroleum Geologists (among others), have produced a booklet on evolution and the fossil record that can be downloaded as a PDF file. This booklet was written for the general public by people who have worked with the fossil record throughout their careers, and was thoroughly reviewed by other professional geologists and paleontologists.

DOWNLOAD the 1 MB PDF file Evolution and the Fossil Record by Pojeta and Springer.

Read the statement on evolution by the Baylor University Department of Biology.

View the web version of the report Science and Creationism: A View from the National Academy of Sciences, Second Edition (1999), published by the U.S. National Academy of Sciences

( or explore other resources about evolution from the National Academy's web site

You can also access position statements and other web resources from the American Geological Institute, the Geological Society of America, the American Geophysical Union, and the American Association for the Advancement of Science.

References and suggested reading

Cairns-Smith, A.G., 1985, Seven clues to the origin of life: Cambridge, UK, Cambridge University Press (Canto edition, 1990), 131 p., ISBN 0-521-39828-2.

Carroll, Sean B., 2005, Endless forms most beautiful: The new science of evo devo and the making of the animal kingdom: New York, W.W. Norton & Co., 350 p., ISBN 0-393-06016-0.

Cooper, J.D., Miller, R.H., and Patterson, J., 1986, A trip through time -- principles of historical geology: Columbus, Ohio, Merrill Publishing Company, 469 p., ISBN 0-675-20140-3.

Dawkins, R., 1995, River out of eden -- a Darwinian view of life: New York, Basic Books, 172 p., ISBN 0-465-01606-5.

Dyson, F., 1999, Origins of life [2nd edition]: Cambridge, UK, Cambridge University Press, 100 p., ISBN 0-521-62668-4.

Eldredge, N., 2000, The pattern of evolution: New York, W.H. Freeman and Company, 219 p., ISBN 0-7167-3963-1.

Emiliani, C., 1992, Planet Earth -- cosmology, geology, and the evolution of life and environment: Cambridge, UK, Cambridge University Press, 717 p., ISBN 0-521-40949-7.

Gould, S.J., 1989, Wonderful life -- the Burgess shale and the nature of history: New York, W.W. Norton & Company, 347 p., ISBN 0-393-02705-8.

Kardong, K.V., 2005, An introduction to biological evolution: New York, McGraw-Hill Higher Education, 322 p., ISBN 0-07-238579-0.

Lewin, R., and Foley, R.A., 2004, Principles of human evolution [2nd edition]: Oxford, UK, Blackwell Publishing, 555 p., ISBN 0-632-04704-6.

Marks, J., 2002, What it means to be 98% chimpanzee -- apes, people, and their genes: Berkeley, California, University of California Press, 312 p., ISBN 0-520-24064-2.

Miller, K., 2000, Finding Darwin's God: Harper Collins Publishers, 352 p., ISBN 0060930497

Olson, S., 2002, Mapping human history -- genes, race and our common origins: New York, Mariner Books, 292 p., ISBN 0-618-35210-4.

Pojeta, J., Jr., and Springer, D.A., 2001, Evolution and the fossil record: Alexandria, Virginia, American Geological Institute, 27 p., ISBN 0-922152-57-8,

Schwartz, J.H., 1999, Sudden origins -- fossils, genes, and the emergence of species: New York, John Wiley & Sons, 420 p., ISBN 0-471-37912-3.

Scott, E.C., 2004, Evolution vs. creationism -- an introduction: Berkeley, University of California Press, 272 p., ISBN 0-520-24650-0.

Stanley, S.M., 1986, Earth and life through time: New York, W.H. Freeman and Company, 690 p., ISBN 0-7167-1677-1.

Wells, S., 2002, The journey of man, a genetic odyssey: New Jersey, Princeton University Press, 224 p., ISBN 0-691-11532-X.

The information on this page was written and approved by the faculty of the Geology Department at Baylor University.