The enormous size of these dinosaurs will astound you.
The Largest Dinosaurs That Ever Existed
In terms of mass, the largest animal on Earth is the blue whale (Balaenoptera musculus), weighing around 136 tons and measuring over 30 meters long. However, the living conditions in the ocean are vastly different from those on land. Today, the largest land animal is the elephant, but if we look back to prehistoric times, there were creatures far larger than elephants, specifically the dinosaurs from the Mesozoic era (about 252 million to 66 million years ago).
1. Dreadnoughtus
This is the largest dinosaur, measuring approximately 26 meters long. (Image: Britannica).
Dreadnoughtus is believed to be the largest dinosaur on Earth, with an estimated total length of about 26 meters (approximately 85 feet) and a mass estimated at up to 59 tons. Fossils of Dreadnoughtus were discovered in rock quarries in southern Patagonia, Argentina, dating back around 77 million years. They were the size of a house, weighed as much as a herd of elephants, and had a long tail used as a weapon. They consumed a vast amount of plant material.
2. Patagotitan mayorum, the Titanosaur
This may be the largest land animal of all time. (Image: Britannica).
Patagotitan mayorum could be the largest land animal of all time, based on estimates from the fossilized bones found. Archaeologists have discovered thigh bones that measure up to 2.4 meters (8 feet) long. It is believed to weigh around 70 tons and measure 37.2 meters (122 feet) long. However, some researchers think these estimates might be too high. This species lived approximately 100 to 95 million years ago.
3. Argentinosaurus
Reconstruction of Argentinosaurus at the Carmen Funes City Museum, Plaza Huincul, Neuquen, Argentina. (Image: William Irvin Sellers, Lee Margetts, Rodolfo Aníbal Coria, Phillip Lars Manning).
Argentinosaurus was scientifically recognized in 1993. Evidence of it was initially discovered in 1987 when a fossil the size of an adult human was excavated on a farm in Argentina. The farm owner thought the fossil was a large piece of petrified wood, and it wasn’t until 1993 that it was reclassified as a single vertebra belonging to a new dinosaur species.
Although no complete skeleton of Argentinosaurus has been found, estimates of its length (based on predictions of the remaining body size using existing fossils) range from 37 to 40 meters (approximately 121 to 131 feet), and it is thought to weigh between 90 to 100 tons. According to these measurements, Argentinosaurus is the largest dinosaur and the largest land animal known.
4. Saltasaurus
Saltasaurus, a dinosaur from the Cretaceous period, belongs to the Titanosaur group. (Image: Mark Turner/Dreamstime.com).
Saltasaurus is named after the city of Salta in northern Argentina, where it was discovered. This species was first described in 1980 and is considered small compared to other Titanosaurs, measuring only 12.2 to 12.8 meters (approximately 40 to 42 feet) long and weighing less than 7 tons.
While some dinosaurs relied on their sheer size to deter predators, an analysis of the incomplete fossil collection of Saltasaurus suggests that this species employed a different defense strategy. The body of this titanosaur was covered with bony scales, or armored plates, making it harder for predators to penetrate its flesh.
5. Rapetosaurus krausei
Skull of Rapetosaurus krausei at the Ontario Museum, Toronto, Ontario, Canada. (Image: D. Gordon E. Robertson).
An immature Rapetosaurus krausei was discovered by researchers during an excavation of a hillside in northern Madagascar in 1998. The dig revealed one of the most complete dinosaur skeletons found to date. Additionally, a juvenile skull and an adult skull were also found at the site. Although the juvenile’s skeleton measured only 8 meters (approximately 26 feet) and no adult skeleton was found, paleontologists estimate that the species could grow up to 15 meters as an adult.
6. Austroposeidon magnificus
Austroposeidon magnificus can reach a length of up to 25 meters (82 feet) when fully grown.
In 1953, a portion of the spine and ribs of a dinosaur was excavated from the Presidente Prudente formation on the outskirts of São Paulo. These fossils remained in the museum for over 60 years before Brazilian researchers had the manpower and resources to study them and declared them as belonging to a completely new dinosaur species, the largest among the nine known species in Brazil as of 2016. Among these excavated fossils, Austroposeidon magnificus can reach a length of up to 25 meters (82 feet). The age of the sandstone and mudstone layers containing the fossils indicates that Austroposeidon magnificus lived about 84 to 66 million years ago.
7. Paralititan stromeri
Paralititan stromeri is a giant lizard from the Albian-Cenomanian of Egypt. (Image: Dmitry Bogdanov).
Paralititan stromeri was first described in 2001 after earlier excavations at a site about 300 km (approximately 186 miles) southwest of Cairo, Egypt, revealed thigh bones measuring 1.69 meters long. The discovery of such a large femur led many paleontologists to assert that Paralititan was comparable in size to Argentinosaurus. Estimates of the dinosaur’s length and weight vary: lengths are estimated to range from 25 to 30.5 meters (82 to 100 feet), and weights are estimated between 60 to 75 tons. Paralititan inhabited mangrove swamps during the mid-Cretaceous period, around 94 million years ago.
8. Shingopana songwensis
S. songwensis is one of the smallest dinosaurs on this list. (Image: internet).
Shingopana songwensis was first discovered in August 2017. Its fossil collection consists of vertebrae, ribs, bones from one of the forelimbs, along with a fragment of the lower jaw and pelvic bone found in 2002 at the Galula Formation of the Great Rift Valley in Africa, located in southwestern Tanzania. The rocks containing the fossils date back 100 million to 70 million years ago.
Shingopana is derived from the Swahili word meaning “wide neck,” inspired by the dinosaur’s bulging cervical vertebrae. Measuring only 8 meters (approximately 26 feet) and weighing around 5 tons, S. songwensis is one of the smallest dinosaurs on this list.
