Why is a dog vertebrate?

A dog is a vertebrate because it has a backbone, also known as a spinal column. Here's why that makes it a vertebrate:

* Vertebrates are animals that have a backbone or spinal column, which is a series of bones that forms the central axis of their body. This backbone provides support and structure, allowing for movement and protection of vital organs.

* Dogs, like all mammals, are vertebrates. They have a clearly defined backbone running down their back, which is essential for their posture, movement, and overall body structure.

Other characteristics of vertebrates include:

* Internal skeleton made of bone or cartilage

* Muscles attached to the skeleton for movement

* Brain protected by a skull

* Well-developed nervous system

* Bilateral symmetry (their body can be divided into two equal halves)

So, the presence of a backbone is the key feature that makes a dog a vertebrate.