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Mosaic evolution in an asymmetrically feathered troodontid dinosaur with transitional features.
Xing Xu1, Philip Currie2, Michael Pittman3
1Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.
Nature Communications
|May 3, 2017
Summary
The discovery of Jianianhualong tengi reveals early asymmetrical feathers in troodontid dinosaurs. This finding suggests feather asymmetry was ancestral to the bird group Paraves.
Area of Science:
- Paleontology
- Evolutionary Biology
- Feather Evolution
Background:
- Asymmetrical feathers are linked to flight but also appear in flightless species, marking a key evolutionary event.
- In non-avialan theropods, asymmetrical feathers were previously known only in microraptorine dromaeosaurids.
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