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.

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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