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Related Experiment Video

Updated: Jul 15, 2026

Computer-Generated Animal Model Stimuli

Computer-Generated Animal Model Stimuli

Published on: July 29, 2007

Four-winged dinosaurs from China.

Xing Xu¹, Zhonghe Zhou, Xiaolin Wang

¹Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, P.O. Box 643, Beijing 100044, China. xing_xu@sina.com

|January 24, 2003

Summary

Basal dromaeosaurid dinosaurs likely had four wings and could glide, suggesting an intermediate stage in avian flight evolution. This finding supports the "tetrapteryx" hypothesis for early bird ancestors.

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Area of Science:

Paleontology
Evolutionary Biology
Biomechanics

Background:

The dinosaurian hypothesis of bird origins is widely accepted.
The precise mechanisms and stages of early avian flight evolution remain debated.

Purpose of the Study:

To investigate the flight capabilities of basal dromaeosaurid dinosaurs.
To provide evidence for an intermediate stage in the evolution of bird flight.

Main Methods:

Analysis of fossil evidence from basal dromaeosaurid dinosaurs.
Comparative anatomical studies.

Main Results:

New evidence suggests basal dromaeosaurids were four-winged.
These dinosaurs likely possessed gliding capabilities.

Conclusions:

Basal dromaeosaurids represent a potential intermediate stage in the evolution of flight.
The findings support the "tetrapteryx" (four-winged) stage hypothesis for avian ancestors.