Kentrosaurus

Kentrosaurus was a medium-sized stegosaurid that roamed what is now Tanzania during the Late Jurassic period, roughly 155-150 million years ago. Unlike its more famous relative Stegosaurus, which bore broad plates along its back, Kentrosaurus featured a striking arrangement of small plates near its neck that transitioned into long, sharp paired spines running down its back and tail. An additional pair of spines projected sideways from its shoulders, creating an impressive defensive array.

This herbivore likely browsed on low-growing vegetation, as its small head positioned close to the ground was poorly suited for reaching high foliage. Its narrow, beaked snout suggests it may have been a selective feeder, choosing specific plants rather than bulk-feeding like some larger herbivores. The brain was famously tiny even by dinosaur standards, though the old myth of a 'second brain' in its hip region has been thoroughly debunked.

Kentrosaurus was discovered during the remarkable Tendaguru expeditions conducted by German paleontologists between 1909 and 1913. Edwin Hennig formally named and described the species in 1915. These expeditions, which employed hundreds of local workers, unearthed an extraordinary dinosaur fauna including Giraffatitan and Elaphrosaurus. The Kentrosaurus material includes bones from multiple individuals, giving scientists a relatively good understanding of this animal.

Recent phylogenetic analyses have challenged the long-held view that Kentrosaurus was a 'primitive' stegosaur. Instead, it appears to be a fairly derived member of Stegosauridae, closely related to the North American Stegosaurus. This suggests that stegosaurids had achieved a near-global distribution by the Late Jurassic, with sophisticated members on multiple continents.