Ornithere: Difference between revisions

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Although nearly all living saucebacks have mandibles (or "tusks"), the mandibles of the jewel-eyed saucebacks are considerably more mandible-like than those of nearly any other sauceback, closely resembling insect mandibles or sideways beaks and even being pigmented. These are used to grab, tear, or crush their food.

The oral ring--a ring of chitinous teeth present in the mouths of all beastworms (and which was ancestral to all "arthropod-like" binucleids)--is comparatively far more basal in anatomy, though the teeth themselves commonly have serrations (which are absent in most other saucebacks). The teeth aid in both processing food and in pulling it down into the throat to be swallowed.

The oral ring--a ring of chitinous teeth present in the mouths of all beastworms (and which was ancestral to all "arthropod-like" binucleids)--is comparatively far more basal in anatomy, though the teeth themselves commonly have serrations (which are absent in most other saucebacks). The teeth aid in both processing food and in pulling it down into the throat to be swallowed. Some species such as the quail raptor have reduced teeth.

Jewel-eyed saucebacks lack the lips that are present in other saucebacks, as their jaws, so much larger than the pincer-like jaws of more basal saucebacks, completely took over the role of closing the mouth; the lips only got in the way. This comes at a cost; some species cannot close their jaws fully because of secondary adaptations, so their mouths are exposed to open air and more prone to water loss.

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 Although nearly all living saucebacks have mandibles (or "tusks"), the mandibles of the jewel-eyed saucebacks are considerably more mandible-like than those of nearly any other sauceback, closely resembling insect mandibles or sideways beaks and even being pigmented. These are used to grab, tear, or crush their food.
-The oral ring--a ring of chitinous teeth present in the mouths of all beastworms (and which was ancestral to all "arthropod-like" binucleids)--is comparatively far more basal in anatomy, though the teeth themselves commonly have serrations (which are absent in most other saucebacks). The teeth aid in both processing food and in pulling it down into the throat to be swallowed.
+The oral ring--a ring of chitinous teeth present in the mouths of all beastworms (and which was ancestral to all "arthropod-like" binucleids)--is comparatively far more basal in anatomy, though the teeth themselves commonly have serrations (which are absent in most other saucebacks). The teeth aid in both processing food and in pulling it down into the throat to be swallowed. Some species such as the quail raptor have reduced teeth.
 Jewel-eyed saucebacks lack the lips that are present in other saucebacks, as their jaws, so much larger than the pincer-like jaws of more basal saucebacks, completely took over the role of closing the mouth; the lips only got in the way. This comes at a cost; some species cannot close their jaws fully because of secondary adaptations, so their mouths are exposed to open air and more prone to water loss.

Ornithere: Difference between revisions

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