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What defines a dinosaur?

  1. Jul 17, 2007 #1
    That is, what distinguishes dinosaurs from other reptiles that existed at the same time, or which still exist, such as crocodiles?

    People do not normally consider the crocodiles to be dinosaurs, despite the fact that they appeared before many other reptiles which have since gone extinct and which are considered dinosaurs.

    Does the fact that they still exist automatically put them in a different classification?
  2. jcsd
  3. Jul 17, 2007 #2


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    Morphology - dinosaurs had different morphologies than such reptiles. Classification used to go along the lines of which animals had X morphology and which animals had Y morphology. This way of classification is an arbitrary social construct, but it usually consistent with the genetic evidence (though there are notable exceptions). Nowadays we have access to genetic analysis, which could change our possible ways of classification.
  4. Jul 17, 2007 #3


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    Its long been held that several of the Dinosaurids had a warm blooded system. They've evolved into birds. One documented case is the famous T-Rex which we see today as the Chicken.

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