Homology

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Homology involves the theory that macroevolutionary relationships can be demonstrated by the similarity in the anatomy and physiology of different animals. [1]An example of a homology argument would be that organisms that are genetically similar have common ancestry.[2]

Creationist Scientists View

Creationist scientist assert the the following: the homology argument is not a legitimate argument for the evolutionary view; the homology argument has problems; and homology is best explained by creation according to a common plan. [3][4][5][6]

In particular, creationist scientists assert the the widely cited chimp/human DNA homology argument is invalid. [7][8]

Christian apologist JP Holding wrote regarding the homology argument:


Homologous structures, far from pointing away from a designer of infinite wisdom, would have indicated to readers of the Bible in their time a designer who did indeed possess infinite wisdom and mastery over His creation. It is only because modern persons have arbitrarily decided that a certain degree of what they see as ‘originality’ is a proper means value that the evolutionists’ argument carries any apparent force.

To frame our argument against the evolutionists’ misuse of homologous structures requires us to have an understanding of certain values critical to ancient persons. Roman literature of the New Testament period tells us that ‘(t)he primary test of truth in religious matters was custom and tradition, the practices of the ancients.’ In other words, old was good, and innovation was bad. Change or novelty was ‘a means value which serves to innovate or subvert core and secondary values.’

By itself, this demolishes one part of the evolutionists’ argument and makes it, clearly, a case of arbitrary imposition of modern values. In a context such as the above, ‘radically different design’ would have indicated to an ancient reader either no deity, or else a deity whose means was chaos and instability, or a deity who did not have mastery over creation.[9]

Evolutionary Science View

Biologists have noted that many (apparently unrelated) species of animals share common characteristics:

  • Dolphins, oceanic sharks, tuna fish, and the extinct ichthyosaurs, which all share a streamlined fishlike form, for their swift swimming predatory lifestyle. Tuna, ichthyosaurs, and certain oceanic sharks even have elevated body temperatures, just like the warm-blooded dolphin, supposedly to facilitate their high levels of activity, even though fish and reptiles are otherwise almost entirely cold-blooded.
  • Hedgehogs, echidnas and certain types of Madagascan tenrecs - though widely separated geographically, all have a coat of protective spines and a prehensile snout ideal for snuffling for invertebrates.
  • Penguins of the Southern hemisphere and auks of the Northern hemisphere both live by chasing fish underwater, using their short stubby wings to fly beneath the waves.
  • The eye of an octopus and human - both contain a retina, a cornea, an iris, a lens and are fluid filled. Some differences do exist - the photo receptors in the human are 'backwards' - catching light reflected off the back of the retina. Additionally, the eye of an octopus is a modification of the skin, while the eye of a human is an extension of the brain.[10][11]

Darwin found evidence for his theory in examples of "convergent evolution", when (as he surmised) the same "adaptations" have "evolved independently" in different lineages of species under similar selection pressures. [12]

References

  1. http://www.answersingenesis.org/tj/v15/i1/homology.asp
  2. http://www.answersingenesis.org/creation/v19/i1/dna.asp
  3. http://www.answersingenesis.org/home/area/cfol/ch1-homology.asp
  4. http://www.answersingenesis.org/creation/v14/i2/homology.asp
  5. http://www.answersingenesis.org/tj/v15/i1/homology.asp
  6. http://www.answersingenesis.org/creation/v14/i2/evolution.asp
  7. http://www.answersingenesis.org/creation/v19/i1/dna.asp
  8. http://www.answersingenesis.org/articles/am/v1/n2/human-and-chimp-dna
  9. http://www.creationontheweb.com/content/view/4781
  10. octopus eye
  11. Comparative Analysis of Gene Expression for Convergent Evolution of Camera Eye Between Octopus and Human
  12. Instant Expert: Evolution