Origin of whales from early artiodactyls: hands and feet of Eocene Protocetidae from Pakistan.
نویسندگان
چکیده
Partial skeletons of two new fossil whales, Artiocetus clavis and Rodhocetus balochistanensis, are among the oldest known protocetid archaeocetes. These came from early Lutetian age (47 million years ago) strata in eastern Balochistan Province, Pakistan. Both have an astragalus and cuboid in the ankle with characteristics diagnostic of artiodactyls; R. balochistanensis has virtually complete fore- and hind limbs. The new skeletons are important in augmenting the diversity of early Protocetidae, clarifying that Cetacea evolved from early Artiodactyla rather than Mesonychia and showing how early protocetids swam.
منابع مشابه
New Protocetid Whale from the Middle Eocene of Pakistan: Birth on Land, Precocial Development, and Sexual Dimorphism
BACKGROUND Protocetidae are middle Eocene (49-37 Ma) archaeocete predators ancestral to later whales. They are found in marine sedimentary rocks, but retain four legs and were not yet fully aquatic. Protocetids have been interpreted as amphibious, feeding in the sea but returning to land to rest. METHODOLOGY/PRINCIPAL FINDINGS Two adult skeletons of a new 2.6 meter long protocetid, Maiacetus ...
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متن کاملTransition of Eocene Whales from Land to Sea: Evidence from Bone Microstructure
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ورودعنوان ژورنال:
- Science
دوره 293 5538 شماره
صفحات -
تاریخ انتشار 2001