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Teeth in ichthyornis (class: aves).

L D Martin, J D Stewart

Science (New York, N.Y.)

|March 25, 1977

Summary

This summary is machine-generated.

Toothed birds like Ichthyornis and Hesperornis had flattened teeth. New fossils suggest Ichthyornis teeth were in grooves, not sockets, potentially varying with age.

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Area of Science:

Paleontology
Evolutionary Biology
Vertebrate Zoology

Background:

Hesperornis and Ichthyornis are extinct toothed birds.
These birds, along with Archaeopteryx, possessed unique flattened teeth with expanded roots.
Previous understanding suggested Ichthyornis teeth were socketed, similar to Archaeopteryx.

Purpose of the Study:

To investigate the tooth implantation in Ichthyornis.
To compare tooth morphology and implantation across Hesperornis, Ichthyornis, and Archaeopteryx.
To determine if tooth socket presence in birds is age-dependent.

Main Methods:

Comparative analysis of fossilized bird dentition.
Examination of new Ichthyornis fossil specimens.
Morphological assessment of tooth roots and jaw structures.

Main Results:

New Ichthyornis specimens reveal teeth were set in a groove, not sockets.
This contrasts with previous reports and aligns with Hesperornis tooth implantation.
The studied Ichthyornis fossils were from an adult, but not aged, individual.

Conclusions:

Tooth implantation in Ichthyornis appears to be a groove, not socket, type.
The presence or absence of tooth sockets in birds might be influenced by age.
This finding offers new insights into avian dental evolution.