In a historic auction, Ken Griffin, the hedge fund billionaire, has purchased a Stegosaurus fossil for a record-breaking $44.6 million. What Happened: The 150-million-year-old dinosaur, affectionately named “Apex,” was auctioned off at Sotheby’s on Wednesday. The sale price is the highest ever paid for a fossil at an auction, reported The Wall Street Journal. Griffin, the 55-year-old founder and CEO of Citadel, expressed his intention to lend “Apex” to a U.S. museum. The dinosaur was discovered by commercial paleontologist Jason Cooper on his property in Dinosaur, Colo., two years ago. The ske…