Stephen Matheson presents common descent by evolution as the best explanation for the universal pattern found in tetrapod limbs. He discusses initially the evolution and development of limbs in specifically vertebrate tetrapods. He looks at the question of origins and further digs into amazing fossil discoveries. He then gives evidence of evolution from fish to tetrapods by discussing the similarities in the anatomy, development, and genetic systems associated with this amazingly common pattern in vertebrate appendages.
  • New Limbs from Old Fins, Part 1

    | Stephen Matheson
    Blog Post
    New Limbs from Old Fins, Part 1 | Stephen Matheson

    Animals seem to be built in very similar ways. It's as though some kind of master plan has been tweaked over and over, to make a huge collection of variations on a theme. Read More >

    Going Deeper PART 1 of 6
  • New Limbs from Old Fins, Part 2: Comparative Anatomy

    | Stephen Matheson
    Blog Post
    New Limbs from Old Fins, Part 2: Comparative Anatomy | Stephen Matheson

    Critics of evolution sometimes portray the theory as an untestable conjecture. But the hunt for the earliest tetrapods was an effort to test a hypothesis that had generated a predicti... Read More >

    Going Deeper PART 2 of 6
  • New Limbs from Old Fins, Part 3: Homology

    | Stephen Matheson
    Blog Post
    New Limbs from Old Fins, Part 3: Homology | Stephen Matheson

    In some sense, a limb is a fin or, more specifically, a modified fin. In biology, there is a specific term for this kind of relationship. It's called homology. Read More >

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  • New Limbs from Old Fins, Part 4: Gene Expression

    | Stephen Matheson
    Blog Post
    New Limbs from Old Fins, Part 4: Gene Expression | Stephen Matheson

    Animals as different as fish and mice are sketched out in form by the expression of the same genes. The patterning of tetrapod limbs has become a classic example. Read More >

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  • New Limbs from Old Fins, Part 5

    | Stephen Matheson
    Blog Post
    New Limbs from Old Fins, Part 5 | Stephen Matheson

    Until quite recently, there was compelling evidence that the development of hands and feet involved processes differing from fins. However new data has pointed to a different conclusi... Read More >

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  • New Limbs from Old Fins, Part 6

    | Stephen Matheson
    Blog Post
    New Limbs from Old Fins, Part 6 | Stephen Matheson

    We'll conclude our series by addressing questions that have come up along the way and by looking closely at the meaning of purpose and design in the context of evolutionary explanatio... Read More >

    Going Deeper PART 6 of 6