frontoparietals
The frontoparietal bones, also known as the frontal and parietal bones respectively, are paired bones that form a significant portion of the skull's roof and sides. In many vertebrates, particularly mammals, these bones fuse together during development to form a single, strong protective structure for the brain. The frontal bone forms the forehead and the anterior part of the cranial vault, while the parietal bones contribute to the upper and posterior regions of the skull. The suture that typically separates the frontal and parietal bones in adults is called the coronal suture, and the suture that separates the two parietal bones is the sagittal suture. In the developing skull of infants, these sutures are not fully fused, allowing for some flexibility and molding during birth. The fontanelles, or soft spots, are unossified areas found at the junctions of these sutures. The frontoparietal region plays a crucial role in protecting the brain from external trauma and provides attachment points for various muscles of the head and neck. Evolutionary changes in the size and fusion patterns of these bones reflect adaptations in brain size and cranial morphology across different species.