Explaining Dinosaurs on Instagram: "Trix the T. rex is the nickname given to one of the most complete and best-preserved Tyrannosaurus rex fossils ever discovered. She was found in Montana in 2013 and is believed to have lived about 67 million years ago. Scientists think Trix was an adult female, possibly over 30 years old when she died, which is very old for a T. rex. Her bones show signs of injuries and healing, giving researchers rare insight into how these dinosaurs survived brutal lives. To