How many cervical vertebrae does a field mouse have? - briefly
A field mouse possesses seven cervical vertebrae, the same count found in the majority of mammalian species. This uniformity reflects the conserved vertebral pattern of the neck region across mammals.
How many cervical vertebrae does a field mouse have? - in detail
Field mice possess the typical mammalian complement of seven cervical vertebrae. The series, designated C1 through C7, follows the standard pattern observed in most placental mammals.
- C1 (atlas) – supports the skull, lacks a vertebral body, and permits nodding motions.
- C2 (axis) – bears the odontoid process (dens) that articulates with the atlas, enabling rotational movement of the head.
- C3–C7 – cylindrical bodies with transverse processes that anchor neck muscles, allowing flexion, extension, and lateral bending.
Developmentally, these vertebrae arise from the first seven somites of the cervical region during embryogenesis. Their morphology in field mice mirrors that of other small rodents, providing a balance between flexibility for foraging and stability for rapid locomotion.
Comparative data show that while most mammals retain seven cervical vertebrae, a few rodent species exhibit deviations (e.g., some members of the family Muridae display six). Field mice, however, conform to the conserved seven‑vertebrae arrangement, reflecting evolutionary constraints on neck structure.
The cervical vertebrae also house the spinal cord segments that innervate forelimb muscles and sensory receptors in the head, underscoring their critical role in coordination and environmental interaction.