The Prehistoric Giants Hall of Fame
What were the largest species of all time? Does the Tyrannosaurus rex make the list?
- By Brian Switek
- Smithsonian magazine, April 2012
Titanoboa was one gigantic snake. It lived around 58 to 60 million years ago, a scant several million years after the mass extinction that wiped out the dinosaurs. It could grow 42 feet or more in length and weigh more than a ton, vastly outslithering the previous fossil record holder, a 40-million-year-old, 33-foot-long snake called Gigantophis. But Titanoboa is just one proud inductee in the Prehistoric Giants Hall of Fame. Meet the other record-holders.
Of all the dinosaur superlatives, “biggest dinosaur ever” is one of the most prized. The trouble is that we don’t really know who deserves the title. Sauropods like Apatosaurus (once known as “Brontosaurus”) and Diplodocus, both at roughly 70 feet long, seemed to be the champions during the 19th century, but since then a variety of even bigger sauropods has been found. The trouble is that the top contenders have been found only in fragments, so their absolute lengths are a matter of estimation.
At the moment, the largest known dinosaur seems to be Argentinosaurus, a long-necked sauropod that lived 94 million years ago in Argentina. This massive creature is estimated to have stretched 100 feet long and weighed more than 73 tons. Other contenders in the roughly 100-foot range are Supersaurus, Sauroposeidon and Futalognkosaurus.
But one dinosaur may have been much, much bigger. In 1878, paleontologist Edward Drinker Cope gave the name Amphiocoelias fragillimus to a dinosaur represented by a five-foot-high neural arch, the top bit of a single vertebra. This must have belonged to an enormous dinosaur, but no other bones were ever found and this single specimen mysteriously disappeared more than a century ago. Paleontologist Kenneth Carpenter estimated that Amphiocoelias may have been anywhere from 130 to 200 feet long and weighed over 100 tons. Was this Jurassic giant truly the biggest dinosaur—and biggest animal—of all time? Until someone finds better fossils, we may never know.