Alamosaurus Facts
| Diet | Herbivore |
| Height | 4.5m |
| Length | 21m |
| Weight | 25 tonnes |
| Speed | 15 km/h |
| Environment | Land |
| Era | Cretaceous |
| Period | Late Cretaceous |
| Type | Sauropod |
| Location | North America |

| Diet | Herbivore |
| Height | 4.5m |
| Length | 21m |
| Weight | 25 tonnes |
| Speed | 15 km/h |
| Environment | Land |
| Era | Cretaceous |
| Period | Late Cretaceous |
| Type | Sauropod |
| Location | North America |
Alamosaurus was a massive sauropod dinosaur that lived during the final stages of the Late Cretaceous period, around 72 to 66 million years ago. This enormous herbivore represents something quite remarkable in dinosaur history - it was one of the last and largest sauropods to roam North America, arriving after these long-necked giants had been absent from the continent for nearly 30 million years.
Measuring up to 21 metres in length and standing 4.5 metres tall at the hip, Alamosaurus was truly colossal, weighing an estimated 25 tonnes. Like other sauropods, it possessed the classic features of a long neck, small head, massive body, and lengthy tail. Its powerful legs supported its enormous bulk as it wandered across the ancient landscapes of what is now the southwestern United States and northern Mexico.
As a herbivore, Alamosaurus used its long neck to reach vegetation that other dinosaurs couldn't access, stripping leaves and branches from tall trees. Its peg-like teeth were perfect for grasping plant material, which was then swallowed whole and processed in its massive gut. The dinosaur likely travelled in herds, creating thunderous footsteps as these giants moved across the Cretaceous plains.
What makes Alamosaurus particularly fascinating is that it probably represents an immigrant population, possibly arriving from South America or Asia. This suggests that even in the final chapter of the dinosaur age, these magnificent creatures were still spreading to new continents and adapting to different environments.
Alamosaurus was distinguished by its enormous size, being one of the largest dinosaurs ever found in North America. It had a relatively shorter neck compared to some other sauropods, with a robust build and particularly massive limb bones that supported its tremendous weight.
Alamosaurus likely lived in herds for protection and social interaction, as evidenced by multiple fossil discoveries in the same geological formations. These gentle giants would have spent most of their time feeding, requiring enormous quantities of plant material daily to sustain their massive bodies.
| Phylum | Chordata |
| Class | Saurischia |
| Family | Saltasauridae |
| Genus | Alamosaurus |
Alamosaurus was first described by Charles Whitney Gilmore in 1922. The original fossils were discovered at San Juan Basin, New Mexico, USA.