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60 million years Oldest Elephant Relative Found
最早大象近親化石六千萬年前摩洛哥找到
Scientists have discovered fossilized remains of the oldest known elephant relative, dating back 60 million years.
The fossils were found in Morocco. Called Eritherium azzouzorum, the animal would not have looked much like an elephant. It was just 1.6 to 2 feet (50 to 60 cm) long and weighed 9 to 11 pounds (4 to 5 kg).
The animal's relation to elephants was determined via analysis of the specimen's teeth and skull. While it lacked a trunk, the animal had an enlarged first incisor, which researcher Emmanuel Gheerbrant of the National Museum of Natural History in Paris, France, says represents a primitive tusk. It was much smaller than the tusks of today's elephants.
"The trunk evolved with the modern elephant group, called elephantiform, at the beginning of the Oligocene," which extends from 33.7 million to 23.8 million years ago, Gheerbrant told LiveScience.
The fossil mammal was found in the same area that yielded the then-oldest elephant relative called Phosphatherium escuilliei, which dated back 55 million years.
The newly identified species extends the record of the Proboscidea order (whose sole survivors today are modern elephants) back to the Late Paleocene.
The research, published in the June 22 issue of the journal Proceedings of the National Academy of Sciences, was financially supported by the Collaboration Agreement with the Ministère de l'Energie et des Mines, the Office Cherifien des Phosphates of Morocco, Universities Cadi Ayyad (Marrakech) and Chouaîb Doukkali (El Jadida).
http://www.livescience.com/animals/090622-ancient-elephant.html
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