Dilophosaurus, an early Jurassic theropod, which roamed North America approximately 186 million years ago, was one of the largest predators of its time. Understanding its true scale is often a point of curiosity, as popular culture has sometimes presented differing impressions of its dimensions. This article explores the actual size of Dilophosaurus based on scientific evidence.
The True Size of Dilophosaurus
Scientifically, Dilophosaurus wetherilli was a sizable predator, typically estimated to be around 7 meters (23 feet) in length. Its height is generally estimated to be between 1.75 to 2.25 meters (5.7 to 7.4 feet) at the hip. The weight of Dilophosaurus is estimated to be approximately 400 kilograms (880 pounds). These measurements are primarily derived from fossil evidence, with the most complete specimen, UCMP 37302, serving as the holotype and a key basis for these reconstructions. While impressive, Dilophosaurus was slender and lightly built compared to some of the much larger theropods that evolved later in the Mesozoic Era.
Unearthing Dilophosaurus’s Dimensions
Paleontologists use various methods to determine the size of extinct dinosaurs from fossil records. One common approach involves skeletal reconstruction, where available bones are assembled, and missing parts are inferred based on comparative anatomy with related, more complete species. Scaling methods also play a significant role, often by measuring the circumference or length of load-bearing bones like the femur. These measurements are then used in mathematical formulas, sometimes drawing comparisons to living animals, to estimate overall body mass and dimensions. The fragmentary nature of many fossil discoveries means that estimations require informed scientific inference and can sometimes involve a range of possibilities rather than a single exact figure.
Dispelling Size Myths
Popular media, particularly the film Jurassic Park, created misconceptions about Dilophosaurus size and characteristics. The movie depicted Dilophosaurus as much smaller than its real-life counterpart, roughly 1 meter tall and 2.6 meters long. In reality, Dilophosaurus was significantly larger, comparable to a brown bear in weight but much longer in stature. Furthermore, the cinematic version introduced fictional traits such as a frilled neck and the ability to spit venom, neither of which has any support in the fossil record. Scientific evidence indicates no anatomical structures that would have supported a neck frill or venom glands.
Comparing Dilophosaurus’s Stature
Dilophosaurus was approximately the length of a small bus. Its weight of about 400 kilograms is comparable to that of a large polar bear. This makes it a substantial animal, far larger than many modern terrestrial predators. When compared to other well-known dinosaurs, Dilophosaurus was smaller than later giants like Tyrannosaurus rex or Allosaurus. However, it was considerably larger than many earlier theropods such as Coelophysis, which measured around 3 meters (9.8 feet) in length. Dilophosaurus stood as the largest known land animal in North America during the Early Jurassic period, making it an apex predator in its ecosystem.