It's not often that scientists say they've found a new dinosaur, so last week's announcement is a big deal -- in all ways. At 85 feet long and with a weight estimated at 65 tons, it’s the largest prehistoric animal ever discovered. "Everything about this dinosaur is giant," says Professor Kenneth Lacovara at Drexel University in Philadelphia. "The femur (thigh bone) is six feet tall. The upper arm bone, the humorous, is almost as tall as I am. The tail bones are gargantuan. . . . It is by far the best example we have of any of the most giant creatures to ever walk the planet."

He led a team that spent four years unearthing nearly half its skeleton in the Patagonia region of southern Argentina, where the vegetarian beast lived approximately 77 million years ago. The natural science professor explains why he chose name Dreadnoughtus, meaning "no dread" or fear: "With a body the size of a house, the weight of a herd of elephants and a weaponized tail, Dreadnoughtus would have feared nothing. It's time the herbivores (plant-eaters) get their due for being the toughest creatures in an environment."

The discovery led a Utah fossil hunter, author-blogger Brian Switek, to reflect on the ageless appeal of these prehistoric beasts. "We're constantly considering dinosaurs in relation to ourselves and the world we know," he writes in a newspaper essay. "Dinosaurs embody the drastic changes that life on Earth has undergone, and give us access to some of the most powerful truths our species has come to understand – that our planet has an incredibly deep history, that life has changed constantly through time."

Finder says: "It weighed as much as a dozen African elephants or more than seven T. rex. . . . You have this 37-foot-long neck balanced by a 30-foot-long tail." -- Ken Lacovara, associate professor of paleontology at Drexel

Author says: "It is the mystery of the dinosaurs that draws me to them. . . . [They're] creatures unlike just about anything alive today." – Brian Switek, science book writer in Salt Lake City

Journalist says: "Dinosaurs combine the 'once upon a time' appeal of fantasy with the mind-boggling knowledge that these monsters actually walked our earth, when our ancestors were little mammals hopping around trees eating insects." – Serge Schmemann, New York Times