A cheetah is a vertebrate, belonging to the group of animals characterized by the presence of a spinal column. The animal kingdom is broadly divided into two major categories: vertebrates, which possess this internal skeletal structure, and invertebrates, which do not. This fundamental anatomical difference places the cheetah firmly in the former group, alongside all other mammals, birds, reptiles, amphibians, and fish.
The Defining Characteristics of Vertebrates
The classification of a vertebrate is based on shared, complex anatomical features centered around an internal skeleton. The most recognizable of these features is the vertebral column, or backbone, which is a segmented series of bones called vertebrae. This structure provides the main support axis for the body, allowing for large size and complex movement.
The backbone also serves a crucial protective function by encasing the delicate spinal cord, which is the major pathway of the central nervous system. Vertebrates possess a complete internal skeleton, or endoskeleton, that is typically made of bone, or cartilage in some species like sharks. This internal framework supports the body’s mass and provides attachment points for muscles, enabling powerful and coordinated locomotion.
All vertebrates have a distinct head region with a skull, which is a bony or cartilaginous structure that protects the brain. The combination of a protected central nervous system and a strong internal support system allows animals in this group to develop specialized sensory organs and complex behaviors.
Contrasting the Traits of Invertebrates
In stark contrast to vertebrates, invertebrates do not possess a vertebral column or an internal skeleton of bone and cartilage. This lack of an internal support structure means their bodies rely on different methods for maintaining shape and facilitating movement. Invertebrates represent about 97% of all animal species on Earth, demonstrating a vast diversity in form and function.
Many invertebrates, such as insects and crustaceans, utilize a rigid external covering known as an exoskeleton for physical support and protection. This hard shell must be periodically shed and regrown in a process called molting, which leaves the animal temporarily vulnerable. Other invertebrates, like jellyfish and worms, use a hydrostatic skeleton, where the pressure of fluid within the body cavity provides structural integrity.
Due to their alternative support systems, most invertebrates tend to be smaller in size and less complex in body plan than their vertebrate counterparts. While some exceptions exist, such as the giant squid, the majority of the largest and fastest animals are vertebrates. This distinction highlights the evolutionary significance of the internal backbone in supporting larger, more active life forms.
The Cheetah’s Place in the Animal Kingdom
The cheetah (Acinonyx jubatus) is classified as a vertebrate belonging to the Phylum Chordata. Within this phylum, it is placed into the Class Mammalia, identifying it as a warm-blooded animal that nurses its young. The cheetah exhibits all the defining characteristics of a vertebrate, including a skull and a complete endoskeleton.
The cheetah’s famous speed is directly related to its highly specialized and flexible spine. This spine acts like a spring, flexing and extending to allow for the long, powerful strides that propel the cheetah to speeds over 60 miles per hour. This physical capability would be impossible without the robust, yet flexible, internal scaffolding of the vertebral column.
Like all mammals, the cheetah possesses hair or fur covering its body and maintains a constant internal body temperature. Its classification as a vertebrate and a mammal places it within the family Felidae, the cat family, along with lions and domestic cats.