Transitional Fossils

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Transitional Fossils

• Creationists often claim they are missing, but
  the truth is they dont exist.

By Jessica Lovering
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A Common Question

• Evolution-Denyers sometimes ask, Where are the
  transitional fossils?
• But more often they simply accuse, There are NO
  transitional fossils.
• Maybe you will be asked for a specific
  transition, say between a fish and a mammal, and
  you wont know what it is.
• Are there really gaps in the evolutionary record
  that evolutionary biologists are overlooking? No,
  but the question of transitional fossils is much
  more complicated than you know.
• This question was quite valid in Darwins time,
  when the fossil record was fairly incomplete, and
  even Darwin worried that there was not enough
  fossil evidence for his theory. However, a lot
  has been dug up since then and this question is
  really out-dated now.

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The simple answer is, here they are
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• Evolutionary Biologists have a pretty complete
  picture of the evolutionary tree, most of the
  major transitions are understood (reptiles to
  birds, reptiles to mammals, etc.) There have
  been great advances in this area in the past few
  decades with molecular evidence.
• You can go to any Natural History museum to see
  good examples of complete transitional fossils.
  Larger museums have expansive stockrooms filled
  with fossils that are not on display and will let
  the public see them if they inquire.
• Sure, there are specific gaps in the fossil
  record (but not in the molecular record). 99.9
  of the species that ever existed are extinct. It
  takes very specific circumstances for a fossil to
  naturally form from the remains of an animal, we
  shouldnt expect to find a fossil for every
  single species. And of course, we cant find
  fossils for animals without bones.
• Archeologists are finding new fossils every week.
  This past week there was a discovery of a
  massive 300 million year-old fossilized forest in
  Illinois.

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The better answer is to ask more questions

• A Transition between what? Two species, two
  genus, two families ?
• Many Biblical Fundamentalists believe that
  micro-evolution or adaptation is possible within
  kinds, as quoted from the bible. Perhaps Noah
  only took two of each kind of animal, and they
  developed the many varieties after the flood.
  But how do they define kinds a species, a
  genus, a family?
• If there is a transition between two species,
  wouldnt that be a different species, and
  therefore not be a transition?
• How do taxonomists define a species? What makes
  one distinct from another? Is it as obvious as
  the difference between an elephant and a banana?

You never see an elephant give birth to a
banana. -Kent Hovind No, Kent, you dont.
Nobody expects you too.
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How to define speciesWhy is it so hard?

• Textbook Definition the individual organisms of
  a natural population that generally interbreed at
  maturity in the wild and whose interbreeding
  produces fertile offspring. There are, of
  course, many problems with this definition. What
  about animals that dont reproduce sexually?
  What species is a hybrid? What if all you have is
  a fossil? And what about animals in captivity,
  that breed unnaturally and sometimes
  cross-species?
• Paleontologists use morphology in practice to
  place a fossil in the fossil record. This is
  difficult in practice because many species slowly
  evolve over millions of years with hundreds of
  minute changes that might not be apparent in the
  fossil, such as changes in skin,hair, immune
  system, and eyes.

• You can define a species by their unique DNA, but
  this can only be done for extant species or where
  there is preserved genetic material. Neat Fact
  Some geneticists have suggested that for about 1
  million years there was some interbreeding
  between the early ancestors of humans and the
  early ancestors of chimpanzees.
• And what about sub-species? Every breed of
  domestic dog is a sub-species of wolf, but you
  would hardly recognize a teacup poodle and a
  Mastiff as the same species based on looks.

The Liger, pictured above, is the hybrid result
of a Lion father and a Tiger mother.
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Branching vs. Linear Evolution

• Evolution isnt a linear string of ancestors,
  its more like a bush or tree, with many splits,
  branches, offshoots, and dead-ends.
• Humans didnt evolve FROM chimps like this
• Chimpanzee Missing Link Human
• We evolved along with Chimpanzees from
• a common ancestor like this

HOMO NEANDERTHALENSIS
HOMO FLORESIENSIS
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So, Where Are They?

• The best answer to the question of Where are the
  transitional fossils? is simply, At your local
  natural history museum.
• But if your questioner is lacking understanding
  of the concept, it may help to ask them to be
  more specific.
• Are they looking for a linear transition or a the
  crook of two branches?
• Do they desire the transition between two
  species, two subspecies, or two families?
• Do they understand how fossils are formed and how
  difficult it would be to have fossil evidence of
  a change in soft tissue?
• Dont just answer their question, educate them on
  speciation, fossil formation, molecular sampling,
  and hominid evolution.
• If you really need a specific transition or
  series of transitions, say between land whales
  and sea whales, just google it.

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Resources

• Wikipedia Transitional Fossil, Species,
  Evolution
• Human Origins The Fossil Record by Clark Spencer
• History Channel DVD From Ape to Man