Saturday, December 18, 2021

[PaleoOrnithology • 2021] Brevirostruavis macrohyoideus • Novel Evolution of A Hyper-elongated Tongue in A Cretaceous Enantiornithine from China and the Evolution of the Hyolingual Apparatus and Feeding in Birds


Brevirostruavis macrohyoideus
Li, Wang, Stidham, Zhou & Clarke, 2021

 
Abstract
The globally distributed extinct clade Enantiornithes comprises the most diverse early radiation of birds in the Mesozoic with species exhibiting a wide range of body sizes, morphologies, and ecologies. The fossil of a new enantiornithine birdBrevirostruavis macrohyoideus gen. et sp. nov., from the Lower Cretaceous Jiufotang Formation in Liaoning Province, northeastern China, preserves a few important skeletal features previously unknown among early stem and extant birds, including an extremely elongate bony hyoid element (only slightly shorter than the skull), combined with a short cranial rostrum. The long hyoid provides direct evidence for the evolution of specialized feeding in this extinct species, and appears similar to the highly mobile tongue that is mobilized by the paired epibranchials present in living hummingbirds, honeyeaters, and woodpeckers. The likely linkage between food acquisition and tongue protrusion might have been a key factor in the independent evolution of particularly elongate hyobranchials in early birds.


Aves Linnaeus, 1758. 
Enantiornithes Walker, 1981. 

Photograph and line drawing of the skull of the holotype specimen of  Brevirostruavis macrohyoideus (IVPP V13266).

Brevirostruavis macrohyoideus gen. et sp. nov. 

Etymology: The genus name refers to its short rostrum (and bird), and the specific epithet refers to the particularly long hyoid apparatus

Locality and horizon: Xiaotaizi Village, Jianchang County, Liaoning Province, China; Jiufotang Formation, Lower Cretaceous. Age approximately 120 Ma (He et al., 2004).


 Brevirostruavis macrohyoideus with its mouth open to show its long tongue that was used to catch insects or obtain nectar from cone-bearing plants


Zhiheng Li, Min Wang, Thomas A. Stidham, Zhonghe Zhou and Julia Clarke. 2021. Novel Evolution of A Hyper-elongated Tongue in A Cretaceous Enantiornithine from China and the Evolution of the Hyolingual Apparatus and Feeding in Birds. Journal of Anatomy. DOI: 10.1111/joa.13588