RAUL ESPERANTE, PhD

Vertebrate Paleontologist


 Research Scientist

PhD., Loma Linda University, California, 2002

 

Contact

 

    Geoscience Research Institute
    Loma Linda, California 92350 USA
    (909) 558-4548
    (909) 558-4314 FAX

    email: click here

 

 

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Specialty

 

  • Taphonomy of fossil vertebrates        

  • Paleoenvironments

Research Interests

  • Taphonomy of fossil marine mammals

  • Rates of deposition in biogenic sediments

  • Trends in the fossil record

  • Paleoenvironmental reconstruction of basins based of taphonomic and sedimentologic information

Recent projects

  • Taphonomy of fossil whales in the Miocene/Pliocene Pisco Formation, Peru

  • Taphonomy of modern whales in the Colorado River, Delta, Baja California, Mexico

  • Stratigraphy and depositional environments of the vertebrate-bearing Jurassic/Cretaceous and Cretaceous/Tertiary boundaries of the Iberian System, Spain

Selected publications

  • Esperante, Raúl, Brand, L., Poma, A. Fossil baleen whales in the Pisco Formation, Peru: taphonomy and sedimentology. In preparation.

  • Brand, L. Esperante, R. Carvajal, C. Chadwick, A., Poma, O., Alomía, M. DeLucchi, F. Melo, L. Fossil whale taphonomy and constrains on diatom accumulation rate, Miocene/Pliocene Pisco Formation, Peru. In preparation.

  • Esperante, Raúl, Brand, L., Poma, A. Fossil baleen preserved in diatomaceous sediments of the Pisco Formation, southern Peru. In preparation.

  • Esperante, Raúl, Brand, L. 2002. Preservation of baleen whales in tuffaceous and diatomaceous deposits of the Pisco Fm, southern Peru. First International Palaeontological Congress (IPC2002), Geological Society of Australia, Abstracts Number 68, 51.

  • Esperante, Raúl, Brand, L., Chadwick, A., Poma, A. 2002. Taphonomy of fossil whales in the diatomaceous sediments of the Miocene/Pliocene Pisco Formation, Peru. In: Current topics on taphonomy and fossilization, De Renzi, M., Pardo Alonso, M. V., Belinchón, M., Peñalver, E., Montoya, P., Márquez-Aliaga, A. (Editors), Valencia, Spain, pages 337-343.

  • Esperante-Caamano, Raúl, Brand, L., Chadwick, A., DeLucchi, F. 2000. Fossil whales of the Miocene/Pliocene Pisco Formation, Peru: stratigraphy, distribution, and taphonomy. Geological Society of America Annual Meeting, Reno, Nevada, Abstracts with Program 32(7): A499.

  • Esperante-Caamano, Raúl, Brand, L., Chadwick, A., Poma, A. 1999. Taphonomy of fossil whales in the Miocene/Pliocene Pisco Formation, western Peru. Geological Society of America Annual Meeting, Denver, Colorado, Abstracts with Program 31(7): A466.

 

 

FOSSIL WHALES OF THE PISCO FORMATION, PERU

This whale (WCBa-32, Carmen) was only partially excavated, because the sediment was very thick to the posterior part of the skeleton. The up side down skeleton is very well articulated and preservation is excellent, except for the tip mandibles and the premaxillary bone which were exposed and modern erosion caused much deterioration. 

 

The lower jaws, the cervical vertebrae, and the limb bones are all in life position. The vertebral column is articulated and so are the ribs, which show a slight turn over one side caused by the torsion of the carcass after reaching the seafloor. The skull is up side down. One limb is completely missing. Several shark teeth were found associated with this skeleton. 

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This whale (WCBa-20, Fernanda) is up side down, about 9.5 meters long and very well articulated. The two limbs are preserved and in life position. Several tail bones are missing. Eleven shark teeth were associated with this skeleton. 

 

Perhaps the most surprising thing of this specimen was the occurrence of the baleen preserved. The baleen is the filtering organ of Mysticeti whales, which feed on small fish and krill that forms the zooplankton. Since the baleen is not made up of bones, but of keratin (the same material as our fingers and hair), it decays much faster than bones, so it is much more difficult to find it as fossil. In this case, the baleen was preserved on top of the right limb, indicating that the filtering plates moved out of the mouth after the death of the whale, and got preserved by rapid sedimentation.

 

 

 

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Geoscience Research Institute
Loma Linda, California 92350 USA
(909) 558-4548
(909) 558-4314 FAX