Archaeorhynchus lungs preserved? (1 Viewer)

Archaeorhynchus lungs preserved?

This information comes from the Society for Vertebrate Paleontology meeting 2018 in Albuquerque:
http://vertpaleo.org/Annual-Meeting...rogram-book-V4-FINAL-with-covers-9-24-18.aspx

pg. 192:
A SPECIMEN OF ARCHAEORHYNCHUS PRESERVING SIGNIFICANT SOFT TISSUE INCLUDING THE FIRST PROBABLE OCCURRENCE OF FOSSILIZED LUNGS
O'CONNOR, Jingmai, Institute of Vertebrate Paleontology & Paleoanthropology, Beijing, China; MAINA, John, Johannesburg, South Africa; PAN, Yanhong, Nanjing, China; WANG, Min, Institute of Vertebrate Paleontology & Paleoanthropology, Beijing, China; WANG, Xiaoli, Linyi University, Lingyi, China; WANG, Yan, Linyi University, Lingyi, China; ZHENG, Xiaoting, Linyi University, Lingyi, China; ZHOU, Zhonghe, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China

We describe a new specimen of the basal ornithuromorph Archaeorhynchus spathula from the Lower Cretaceous Jiufotang Formation with extensive soft tissue preservation. Although it is the fifth specimen to be described, it is the first to preserve significant traces of the plumage, revealing a pin-tail morphology previously unrecognized among Mesozoic birds but common in extant neornithines. In addition, this specimen preserves the probable remnants of the paired lungs, an identification supported by topographical and macro- and microscopic anatomical observations. The preserved morphology reveals a lung very similar to that of living birds. It indicates that pulmonary specializations such as exceedingly subdivided parenchyma that allow birds to achieve the oxygen acquisition capacity necessary to support powered flight were present in ornithuromorph birds 128 Ma. This is the first documented occurrence of preserved lung soft tissue in a fossil vertebrate Among extant air breathing vertebrates, birds have structurally the most complex and functionally the most efficient respiratory system, which facilitates their highly energetically demanding form of locomotion even in extremely oxygen poor environments. Archaeorhynchus is commonly resolved as the most basal known ornithuromorph bird, capturing a stage of avian evolution in which skeletal indicators of respiration remain primitive yet the lung microstructure appears modern. This adds to growing evidence that many physiological modifications of soft tissue systems (e.g., digestive system and respiratory system) that characterize living birds and are key to their current success may have preceded the evolution of obvious skeletal adaptations traditionally tracked through the fossil record.
Grant Information
National Natural Science Foundation of China (41688103, 41472023, 41372014, 41402017)

News

https://www.sciencenews.org/article/first-scientists-spot-what-may-be-lungs-ancient-bird-fossil

https://www.livescience.com/63880-oldest-fossil-bird-lung.html

Enjoy,

Fred

Xiaoli Wang, Jingmai K. O’Connor, John N. Maina, Yanhong Pan, Min Wang, Yan Wang, Xiaoting Zheng & Zhonghe Zhou, 2018

Archaeorhynchus preserving significant soft tissue including probable fossilized lungs

Proceedings of the National Academy of Sciences of the United States of America. in press. doi:10.1073/pnas.1805803115

http://www.pnas.org/content/early/2018/10/16/1805803115

Significance
Archaeorhynchus spathula is a basal member of the Ornithuromorpha, the lineage that includes neornithines. Although this is the fifth reported specimen, unlike the others it preserves significant soft tissue, revealing a tail morphology previously unknown in Mesozoic birds and an exceptional occurrence of fossilized lung tissue. This identification is based on topographical location and anatomical features revealed mainly by scanning electron microscopy. A structure similar to that in neornithines indicates that the 120-Ma-old Archaeorhynchus may have been capable of acquiring the large quantities of oxygen needed to support powered flight. Skeletal features related to respiration remain primitive, supporting inferences that many physiological adaptations preceded skeletal changes during the evolution of the anatomically modern bird.

Abstract:

We describe a specimen of the basal ornithuromorph Archaeorhynchus spathula from the Lower Cretaceous Jiufotang Formation with extensive soft tissue preservation. Although it is the fifth specimen to be described, unlike the others it preserves significant traces of the plumage, revealing a pintail morphology previously unrecognized among Mesozoic birds, but common in extant neornithines. In addition, this specimen preserves the probable remnants of the paired lungs, an identification supported by topographical and macro- and microscopic anatomical observations. The preserved morphology reveals a lung very similar to that of living birds. It indicates that pulmonary specializations such as exceedingly subdivided parenchyma that allow birds to achieve the oxygen acquisition capacity necessary to support powered flight were present in ornithuromorph birds 120 Mya. Among extant air breathing vertebrates, birds have structurally the most complex and functionally the most efficient respiratory system, which facilitates their highly energetically demanding form of locomotion, even in extremely oxygen-poor environments. Archaeorhynchus is commonly resolved as the most basal known ornithuromorph bird, capturing a stage of avian evolution in which skeletal indicators of respiration remain primitive yet the lung microstructure appears modern. This adds to growing evidence that many physiological modifications of soft tissue systems (e.g., digestive system and respiratory system) that characterize living birds and are key to their current success may have preceded the evolution of obvious skeletal adaptations traditionally tracked through the fossil record.

Fred

Fascinating discovery. . ..

Slab and counterslab of the specimen STM7-11

Enjoy the pictures the supposed lungs are the part in the white square on the counterslab

Fred