Snakes are fascinating and strange animals. The lack of limbs and scaly skin make them look strange to us. Some people even have a largely unfounded fear of them. Because of their strangeness and worm-like build, you may have wondered whether snakes are vertebrates? To do this, of course, you first have to clarify what vertebrates actually are.
How vertebrates are defined
- Vertebrates are, as the word suggests, one of the things that distinguish them is that they have a spine. The biological term for these animals is vertebrata.
- In addition to the spine, they have a bony skull as another important feature, from which the alternative biological term craniota is derived.
- The vertebrates include, in addition to some lesser-known groups of animals, fish, amphibians, reptiles, birds and mammals.
- Vertebrates represent a closed community of descent. This means that all vertebrates descend from a common ancestor.
- Most people know that snakes are reptiles. More precisely, they belong to the scale reptiles (scientifically correct: Squamata), which also includes lizards, monitor lizards, iguanas and chameleons.
- It follows that since reptiles are counted among the vertebrates, snakes are also counted among the vertebrates.
Snakes belong to the scale reptiles and have evolved from ...
The physique of snakes
Snakes are legless lizards. Sometime in the course of her evolution the ancestors of today's snakes reduced their legs.
- The body of a snake is similar to the body of a lizard, only without legs. First of all, it can be divided into head, torso and tail; even if it may be difficult for the untrained eye to distinguish the trunk from the tail.
- The internal anatomy of snakes is basically similar to that of other reptiles. In the head you can find the skull, which surrounds the brain, as well as sensory organs (eyes, ears, nose ...) and the mouth and tongue.
- The trunk contains the spine, muscles and internal organs such as the heart, liver, kidney, etc.
- The tail consists only of the spine and muscles
- The skeleton of the snake consists of the skull and the spine. Since snakes do not have arms or legs, they do not have a limb skeleton. Only in giant snakes (phythons, boas) are tiny remnants of the pelvic bones that are not visible from the outside.
- As in all vertebrates, the spine of the snake consists of individual vertebral bones and ribs that attach to the vertebral bones.
- In contrast to mammals, the spine in snakes is not divided into cervical, thoracic and lumbar vertebrae. Ribs are attached to all vertebral bones. The snakes also lack a breastbone, which is also typical of mammals.
So if you think about the fact that snakes are reptiles, it becomes apparent that snakes must be vertebrates. The common ancestor of all vertebrates has as an evolutionary novelty u. a. a bony spine evolves. This was retained by all descendants, including the snakes. Snakes have only reduced limbs, but otherwise still have a skeleton including a spine.