In February, 1995, Rebecca Lessem (aged 13) and her dad (also known as Dino Don) traveled to the deserts of Argentina to see Argentinosaurus, the world's largest dinosaur, in the company of educator Dinah Zike, photographer Ignacio Salas Humara and dinosaur scientist Dr. Philip Currie. Rebecca filed this report.

After arriving in Plaza Hunicul, a city in the vast openness of Patagonia, we found we were too late. The great Argentinosaurus was dead, and had been for a while. I guessed that it was probably all the flight delays that prevented us from getting there on time.

But we did get to see its bones. Later that day, Dr. Rodolfo Coria of the Museo Carmen Funes in Plaza Huincul took our group out to the dig site, just outside of town. When we got there, I knew that in all the flat miles of desert I would never have discovered a dinosaur.

Rodolfo took us to the excavation, on a sheep ranch beside a highway and near a deserted railroad track, where two men were drilling rock off an Argentinosaurus vertebra. The vertebra was huge, about my height (five feet) and as wide as it was tall. In the ground it looked the size of our kitchen table, though I knew it weighed much more — about one ton.

We then went to Rodolfo's tiny museum in the heart of Plaza Huincul city, where we saw skin imprints of a meat eating dinosaur, fossilized sea creatures, a nest of dinosaur eggs, and most importantly several other huge vertebrae, a sacrum (hip bone) and fibula (shin bone) of Argentinosaurus, which Dr. Coria had excavated.

Just what Argentinosaurus looked like remains a mystery. Since we don't have all the leg bones we don't know its stance. It might have had longer back legs than front legs like a titanosaur  ––  the most common large plant-eaters in South America. But it might have had longer front legs than back legs, like a brachiosaur, which it resembles in the shape of its fibula and sacrum.

Dr. Coria estimates Argentinosaurus to have been nearly the length of Seismosaurus at 115 feet long. But it weighed much more that Seismosaurus, nearly 100 tons. Argentinosaurus was so heavy that its ribs were hollow: a characteristic of birds and meat-eating dinosaurs not seen before in plant-eating dinosaurs.

The next day, we went to an old ranch high up on a steep hill where the largest theropod (carnivorous or meat-eating dinosaur) was found. This giant meat-eater was discovered so recently (1993) that it doesn't have an official name yet. Dr. Coria and Dr. Currie think it was about the size of Tyrannosaurus rex, 45 feet long, though its thigh bone is slightly longer than T. rex's. While we were there, Dinah Zike and I found some natural chalk in a dried-up river bed, and Philip Currie found a goat's skull. We didn't have a chance to dig for bones, but Dr. Coria has already found most of the dinosaur, including its skull and tail.

It was a fun and exciting trip, and I hope to go on many more like it.