Stegosaurus

Stegosaurus stenops

Two staggered rows of large bony plates along the back and a spiked tail, known as a thagomizer, make Stegosaurus stenops instantly recognizable. This Late Jurassic herbivore reached about 9 meters and near 5,000 kilograms, yet its brain was only about the size of a walnut. The plates, richly supplied with blood vessels, may have aided temperature regulation and visual display rather than serving as armor. Othniel Charles Marsh described it in 1877 from Morrison, Colorado, in the fossil-rich beds that lend the Morrison Formation its name, dating to roughly 161 to 145 million years ago. It remains among the most familiar of all plated dinosaurs.

Stegosaurus is famous for its double row of large bony plates along its back and the spiked tail (thagomizer). Despite its large body, its brain was only the size of a walnut. The plates may have been used for thermoregulation and display.

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Physical Description

Measurement	Value	Human Scale
Uzunluk	9.0 m	roughly the length of a large SUV
Height	4.0 m	—
Ağırlık	5.0 t	about the weight of 0.8 elephants

Diet & Feeding

Herbivore

Stegosaurus was a plant-eating dinosaur. Herbivores typically fed on ferns, cycads, conifers, and other vegetation available during their era. Many herbivorous dinosaurs developed specialized teeth and digestive systems for processing tough plant material.

Time Period

Jurassic Late Mesozoic Era

Stegosaurus lived during the Jurassic Late period of the Mesozoic Era, approximately 161,5 to 145,0 million years ago.

One of the most iconic periods for dinosaurs. Giant sauropods like Brachiosaurus and Diplodocus roamed alongside predators like Allosaurus. Archaeopteryx, the earliest known bird, appeared. The Morrison Formation preserves an extraordinary fossil record from this time.

Discovery & Naming

Adlandıran	Othniel Charles Marsh
Keşif Yılı	1877
Keşif Yeri	Morrison, Colorado, USA

Sınıflandırma

Dinosauria → Ornithischia → Thyreophora → Stegosauria → Stegosaurus

Plated dinosaurs

Herbivorous dinosaurs characterized by large bony plates along the back and tail spikes (thagomizer). Most common in the Late Jurassic. Stegosaurus is the best-known member.