Natural Selection and Adaptation

Lecture Part 1

I. Whether species change is an old philosophical question considered by Plato and Aristotle


  1. Plato postulated ideal perfect forms which transcend the "real" world. [Man is to archetypal man as a circle is to circularity]
  2. Aristotle arranged organisms from simple to complex "Scale of Nature" [Man of course at the top of the scale - however no transcendent archetype of man]

    Both Plato and Aristotle believed in unchangeability (immutability) of basic Kinds.

  3. Judeo Christian theology reinforced the idea of immutability. [All living things were created in only a few days by a Supreme Being - no time for change (evolution)]
  4. Carolus Linaeus established "modern" classification based on homologies, but many assumptions were implicated as being biased.
  5. Buffon - original animals of creation may give rise to "Lessor families - conceived by nature".
  6. Lamarck was more right (+) than wrong (-)
+ change did occur - species give rise to other species

+ characteristics are heritable

- all things have a special place in the scale of nature

+ fossils show that simpler animals are found in older (deeper) layers and they must be ancestral to modern forms.

+ change is gradual

- some characteristics acquired over a lifetime are heritable.

Links to other Lectures about evolution include:


page updated March 7 2003