A 67-million-year-old Tyrannosaurus rex fossil named Gus has become the most expensive dinosaur ever sold, fetching a staggering $50.1 million at a Sotheby's auction in New York. One of the most complete T. rex specimens ever discovered, the fossil sparked a fierce bidding war before being snapped up by an anonymous buyer, reigniting debate over whether such extraordinary discoveries belong in private collections or public museums.