 The most notable feature of Acrocanthosaurus was its row of tall neural spines , located on the vertebrae of the neck , back , hips and upper tail , which could be more than 2 @.@ 5 times the height of the vertebrae from which they extended . Other dinosaurs also had high spines on the back , sometimes much higher than those of Acrocanthosaurus . For instance , the unrelated Spinosaurus had spines nearly 2 meters ( 6 @.@ 5 ft ) tall , about 11 times taller than the bodies of its vertebrae . The lower spines of Acrocanthosaurus had attachments for powerful muscles like those of modern bison , probably forming a tall , thick ridge down its back . The function of the spines remains unknown , although they may have been involved in communication , fat storage , or temperature control . All of its cervical ( neck ) and dorsal ( back ) vertebrae had prominent depressions ( pleurocoels ) on the sides , while the caudal ( tail ) vertebrae bore smaller ones . This is more similar to carcharodontosaurids than to Allosaurus . 
