Enantiornithes indet. in Burmese amber (hatchlings)

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Time: Mid-Cretaceous (~99 million years ago)

Region: Kachin State (Hukawng Valley), Myanmar

Formation: Burmese amber

Coloration Data

Isolated avian wings and an exceptionally preserved, articulated enantiornithine hatchling have been recovered entombed in Burmese amber. Visual analysis of the macroscopic pigmentation preserved in the isolated wing specimens demonstrated countershading: the remiges were brown with darker apical tips, and the dorsal contour feathers were deep brown, whereas the ventral side of the wing and the down feathers were pale or white. In addition, a distinct pale spot was present at the base of the alula on both wings. In the near-complete hatchling specimen HPG-15-1, darkly pigmented, bristle-like integumentary structures resembling primitive protofeathers were identified along the legs and tail. Its flight feathers were predominantly brown, accented by pale transverse bars and pale tips.

Method: Direct visual and optical microscopic analysis of preserved pigments under transmitted and reflected light through the transparent amber matrix.

Publications

• Lida Xing, Ryan C. McKellar, Min Wang, Ming Bai, Jingmai K. O’Connor, Michael J. Benton, Jianping Zhang, Yan Wang, Kuowei Tseng, Martin G. Lockley, Gang Li, Weiwei Zhang & Xing Xu (2016)
  Research into the wings of Mesozoic birds preserved in amber.
• Lida Xing, Jingmai K. O'Connor, Ryan C. McKellar, Luis M. Chiappe, Kuowei Tseng, Gang Li, Ming Bai (2017)
  A study of a hatchling that was fully preserved in Burmese amber.

Documents and files

• Xing_et_al_2016.pdf (PDF)
  Study of Mesozoic bird wings preserved in amber.

Reconstructions

Fossils