[dinosaur] Najash fossils reveal evolution of snake skull and body (free pdf)

Ben Creisler
[email protected]

A new paper in open access:

Fernando F. Garberoglio, Sebastián Apesteguía, Tiago R. Simões, Alessandro
Palci, Raúl O. Gómez, Randall L. Nydam, Hans C. E. Larsson, Michael S. Y.
Lee and Michael W. Caldwell (2019)
New fossils from the legged snake Najash reveal the evolutionary origins of
key features of the modern snake skull and body.
Science Advances 5(1): eaax5833
DOI: 10.1126/sciadv.aax5833
https://urldefense.proofpoint.com/v2/url?u=https-3A__advances.sciencemag.org_content_5_11_eaax5833&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=D4zLAQiRVL2a2P4NE6xG15XweXG9Kc0Hg0b_xxwUOPg&s=C-aFRr4aD7ZhTZ1stHczbLyKCPiYjf7zDhArq-sumbk&e= 
Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__advances.sciencemag.org_content_advances_5_11_eaax5833.full.pdf&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=D4zLAQiRVL2a2P4NE6xG15XweXG9Kc0Hg0b_xxwUOPg&s=ewtd047x6TqpMnbiI6w3znXWzhXMKvvEdUEE2pYJY9w&e= 

Snakes represent one of the most dramatic examples of the evolutionary
versatility of the vertebrate body plan, including body elongation, limb
loss, and skull kinesis. However, understanding the earliest steps toward
the acquisition of these remarkable adaptations is hampered by the very
limited fossil record of early snakes. Here, we shed light on the
acquisition of the snake body plan using micro–computed tomography scans of
the first three-dimensionally preserved skulls of the legged snake Najash
and a new phylogenetic hypothesis. These findings elucidate the initial
sequence of bone loss that gave origin to the modern snake skull.
Morphological and molecular analyses including the new cranial data provide
robust support for an extensive basal radiation of early snakes with
hindlimbs and pelves, demonstrating that this intermediate morphology was
not merely a transient phase between limbed and limbless body plans.

News:

New fossils shed light on how snakes got their bite and lost their legs

https://urldefense.proofpoint.com/v2/url?u=https-3A__phys.org_news_2019-2D11-2Dfossils-2Dsnakes-2Dlost-2Dlegs.html&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=D4zLAQiRVL2a2P4NE6xG15XweXG9Kc0Hg0b_xxwUOPg&s=PvzlZH7_TSmvLuARPYqAF1ORvZyLx2GKD9ffhap-ksY&e= 

https://urldefense.proofpoint.com/v2/url?u=https-3A__cosmosmagazine.com_palaeontology_when-2Dsnakes-2Dhad-2Dlegs&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=D4zLAQiRVL2a2P4NE6xG15XweXG9Kc0Hg0b_xxwUOPg&s=Ge0rX3akZhwtobXkO-FtihNZFq-PaP6mdIqTnlfXjrA&e= 

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