New fossils of the giant African crocodyliform Sarcosuchus imperator clarify its skeletal anatomy, growth patterns, size, longevity, and phylogenetic position. The skull has an expansive narial bulla and elongate jaws studded with stout, smooth crowns that do not interlock. The jaw form suggests a generalized diet of large vertebrates, including fish and dinosaurs. S. imperator is estimated to have grown to a maximum body length of at least 11 to 12 meters and body weight of about 8 metric tons over a life-span of 50 to 60 years. Unlike its closest relatives, which lived as specialized piscivores in marginal marine habitats, S. imperator thrived in fluvial environments.
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Supported by the David and Lucile Packard Foundation, the National Geographic Society, and the Pritzker Foundation. We thank C. Abraczinskas for the finished illustrations; A. Beck, A. Britton, C. Brochu, J. Conrad, J. Head, W. Langston Jr., and J. Wilson for comments on the manuscript; B. Barr, B. C. Choudhury, and G. Martin for help in measuring G. gangeticus; A. Britton for measurements of C. porosus; E. Dong, A. Gray, L. Mahler, T. Keillor, R. Masek, and C. Noto for fossil preparation; A. Beck, D. Blackburn, J. Bradshaw, J.-P. Cavigelli, J. Conrad, E. Duneman, D. Dutheil, M. Hettwer, G. Lyon, T. Lyman, J. Marcot, R. Sadleir, G. Wilson, J. Wilson, and D. Varricchio for their contributions during expeditions in 1997 and 2000; and I. Kouada and the government of the Niger Republic for their support of this research.
Volume 294 | Issue 5546
16 November 2001
16 November 2001
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Received: 24 September 2001
Accepted: 16 October 2001
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