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1. The Ediacaran frondose fossil Arborea from the Shibantan limestone of South China

   https://doi.org/10.1017/jpa.2020.43  

   Wang, Xiaopeng ; Pang, Ke ; Chen, Zhe ; Wan, Bin ; Xiao, Shuhai ; Zhou, Chuanming ; Yuan, Xunlai ( November 2020 , Journal of Paleontology)

   Abstract Bituminous limestone of the Ediacaran Shibantan Member of the Dengying Formation (551–539 Ma) in the Yangtze Gorges area contains a rare carbonate-hosted Ediacara-type macrofossil assemblage. This assemblage is dominated by the tubular fossil Wutubus Chen et al., 2014 and discoidal fossils, e.g., Hiemalora Fedonkin, 1982 and Aspidella Billings, 1872, but frondose organisms such as Charnia Ford, 1958, Rangea Gürich, 1929, and Arborea Glaessner and Wade, 1966 are also present. Herein, we report four species of Arborea from the Shibantan assemblage, including the type species Arborea arborea (Glaessner in Glaessner and Daily, 1959) Glaessner and Wade, 1966, Arborea denticulata new species, and two unnamed species, Arborea sp. A and Arborea sp. B. Arborea arborea is the most abundant frond in the Shibantan assemblage. Arborea denticulata n. sp. resembles Arborea arborea in general morphology but differs in its fewer primary branches and lower length/width ratio of primary branches. Arborea sp. A and Arborea sp. B are fronds with a Hiemalora -type basal attachment. Sealing by microbial mats and authigenic cementation may have played an important role in the preservation of Arborea in the Shibantan assemblage. The Shibantan material of Arborea extends the stratigraphic, ecological, and taphonomic ranges of this genus. UUID: http://zoobank.org/554f21da-5f09-4891-9deb-cbc00c41e5f1 

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2. Eocene Fossil Legume Leaves Referable to the Extant Genus Arcoa (Caesalpinioideae, Leguminosae)

   https://doi.org/10.1086/701468  

   Herendeen, Patrick S. ; Herrera, Fabiany ( March 2019 , International Journal of Plant Sciences)
3. A new Early Jurassic (ca. 183 Ma) fossil Lagerstätte from Ya Ha Tinda, Alberta, Canada

   https://doi.org/10.1130/G38808.1  

   Martindale, Rowan C. ; Them, Theodore R. ; Gill, Benjamin C. ; Marroquín, Selva M. ; Knoll, Andrew H. ( February 2017 , Geology)
4. Joint histology in Alligator mississippiensis challenges the identification of synovial joints in fossil archosaurs and inferences of cranial kinesis

   https://doi.org/10.1098/rspb.2017.0038  

   Bailleul, Alida M. ; Holliday, Casey M. ( March 2017 , Proceedings of the Royal Society B: Biological Sciences)
5. Differential growth of the adductor muscles, eyeball, and brain in the chick Gallus gallus with comments on the fossil record of stem‐group birds

   https://doi.org/10.1002/jmor.21622  

   Cerio, Donald G. ; Llera Martín, Catherine J. ; Hogan, Aneila V. C. ; Balanoff, Amy M. ; Watanabe, Akinobu ; Bever, Gabriel S. ( July 2023 , Journal of Morphology)

   The avian head is unique among living reptiles in its combination of relatively large brain and eyes, coupled with relatively small adductor jaw muscles. These derived proportions lend themselves to a trade‐off hypothesis, wherein adductor size was reduced over evolutionary time as a means (or as a consequence) of neurosensory expansion. In this study, we examine this evolutionary hypothesis through the lens of development by describing the jaw‐adductor anatomy of developing chickens,Gallus gallus, and comparing the volumetric expansion of these developing muscles with growth trajectories of the brain and eye. Under the trade‐off hypothesis, we predicted that the jaw muscles would grow with negative allometry relative to brain and eyes, and that osteological signatures of a relatively large adductor system, as found in most nonavian dinosaurs, would be differentially expressed in younger chicks. Results did not meet these expectations, at least not generally, with muscle growth exhibiting positive allometry relative to that of brain and eye. We propose three, nonmutually exclusive explanations: (1) these systems do not compete for space, (2) these systems competed for space in the evolutionary past, and growth of the jaw muscles was truncated early in development (paedomorphosis), and (3) trade‐offs in developmental investment in these systems are limited temporally to the perinatal period. These explanations are considered in light of the fossil record, and most notably the skull of the stem birdIchthyornis, which exhibits an interesting combination of plesiomorphically large adductor chamber and apomorphically large brain.

    

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