Missing link

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The missing link between Google 1.0 and Google 2.0.
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Evolution

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Missing link is an obsolete expression for transitional form. It is generally avoided in scientific discussions as it is suggestive of several misunderstandings about evolution:

  • The old idea of a Great Chain of Being, in which there is a linear progression "upward" presumably ending with mankind, just underneath gods and other divine beings. Concepts of evolution since Darwin recognize, to the contrary, that evolutionary change often involves branching, and that unguided evolution has no preferred "direction".
  • The idea that the fossil record is the only type of evidence which can establish a connection between different life forms. The preponderance of the evidence for evolutionary connections always has been found in living things from the present ("neontology") rather than solely in the fossil record ("palaeontology"). Comparative study of DNA since the elucidation of its structure is just one of the remarkable new lines of investigation.
  • Another mistaken idea is that there is a scandalous gap in the fossil record especially with regard to human evolutionary history. While a hundred years or more ago, there were very few fossils of human precursors. Even as early as the 19th century, there were famous fossils such as Neanderthal (Homo neanderthalensis) and Java man (Homo erectus), and the number has dramatically increased as explorations have concentrated on productive regions in Africa (as suggested by Darwin, but largely ignored at first) since the mid-20th century.
  • The final mistaken idea is that there is precisely one form: the missing link, which makes the connection between the past and the present. Evolution is understood ever since Darwin as an ongoing process in which one can expect many changes, sometimes very small, which can be fully appreciated only in their places in a web of relationships over stretches of time.
  • Another problem is that evolution denialists will simply claim that there is another missing link even when a missing link was found. Let's just say that modern humans are Human 2.0 and some early form of "humans" is called Human 1.0. Evolution denialists would claim that we need to find the missing link of Human 1.5. If Human 1.5 is discovered, that creates two new missing links, Human 1.25 and Human 1.75 that evolution denialists would say need to be discovered. If those two missing links are discovered, then the four new missing links Human 1.125, Human 1.375, Human 1.625 and Human 1.875 would need to be discovered. And so on. The only way to satisfy evolution denialists would be to have a record of all "humans" or even all life that has ever existed. Even if every fossil organism were discovered and categorized, there would still be "missing links" because likelihood that bones become fossilized is very rare since fossilization requires a very specific set of geological conditions.[1]

[edit] See also

[edit] Footnotes

  1. What are the odds of a dead dinosaur becoming fossilized? Paleontologist Gregory M. Erickson of Florida State University explains. (September 16, 2002) Scientific American.
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