FORT WORTH (CBSDFW.COM/AP) — A doctor in North Texas with a passion for paleontology is challenging the federal government after authorities seized a 70 million-year-old dinosaur skull from his fossil collection.

Dr. James Godwin argues that the government waited too long to file a forfeiture claim after it seized the Tyrannosaurus bataar skull that authorities say was among several fossils smuggled illegally out of Mongolia.

skull North Texas Doctor Sues To Keep Dinosaur Skull Seized By Feds

Tyrannosaurus Bataar skeleton in a museum (JOHANNES EISELE/AFP/Getty Images)

Federal investigators say the skull was unearthed from the Gobi Desert between 2000 and 2011 and it traded hands several times before it ended up at a Wyoming store, where Godwin acquired it.

According to the Dallas Morning News , a judge in Fort Worth heard testimony Tuesday in the case and says he’ll rule at a later date.

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