Taphonomy and palaeopathology of two mysticete whales, upper Miocene Pisco Formation, Peru

Abstract

Two mysticete fossil whales from the upper Miocene of the Pisco Formation in Peru are described that show healed bone-fractures in ribs. One specimen is preserved in a tuffaceous diatomaceous siltstone and the other specimen is preserved in siltstone. Both specimens are well preserved, mostly articulated and almost complete. Shark teeth were found associated with one of the skeletons, but both specimens lack any trace evidence for the activity macro-scavengers. We suggest that the cause of bone fracture may have been collision with rocky shores, other wales, or large predators. The fact that the rib fractures healed indicates that the whales did not die due the bone fractures. Sedimentologic and paleontological evidence indicate that they were rapidly buried in the marine platform with well-oxygenated water