Bone Layers

English
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Dr. Nicholas D. Pyenson (Smithsonian Institution) points to fossil invertebrate burrow at Cerro Ballena in 2012.
Drs. David Rubilar Rogers (Museo Nacional de Historia Natural) and Nicholas D. Pyenson (Smithsonian Institution) collect a fossil whale vertebra in the roadcut at Cerro Ballena in 2012.
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