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Related Experiment Video

Updated: Jul 11, 2026

Studying the Neural Basis of Adaptive Locomotor Behavior in Insects

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Published on: April 13, 2011

A devonian tetrapod from north america.

E B Daeschler, N H Shubin, K S Thomson

Science (New York, N.Y.)

|July 29, 1994

Summary

This summary is machine-generated.

A newly discovered early tetrapod fossil from Pennsylvania pushes back the timeline for tetrapods in North America. This finding suggests early tetrapods had advanced limb development and a wide global distribution.

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Area of Science:

Paleontology
Vertebrate Evolution
Devonian Period

Background:

Tetrapods represent a pivotal evolutionary transition from aquatic to terrestrial life.
The early fossil record of tetrapods is crucial for understanding their evolutionary origins and diversification.
The Upper Devonian period marks a critical time for the emergence of early tetrapods.

Purpose of the Study:

To document and describe a new early tetrapod fossil from the Catskill Formation in Pennsylvania.
To extend the known temporal and geographic range of early tetrapods.
To infer the functional morphology and locomotor capabilities of early tetrapods.

Main Methods:

Fossil excavation and preparation.
Comparative anatomical analysis of the pectoral girdle and skeleton.
Paleogeographic reconstruction.

Main Results:

Discovery of an early tetrapod fossil extending the North American temporal range.
Evidence of derived shoulder girdle features indicating well-developed appendicular support and propulsion.
Specialized pectoral skeleton morphology suggesting significant early tetrapod diversity and innovative locomotion.

Conclusions:

Early tetrapods achieved a near-global equatorial distribution by the end of the Devonian.
Appendicular locomotion was sophisticated even in the earliest tetrapods.
The diversity and locomotor strategies of early tetrapods were likely underestimated.