Definition: A vertebrate is an animal that has cartilaginous
or bony vertebrae that surround a nerve cord and a skull that protects
the brain. Vertebrates all belong to a taxonomic class of animals known
as the Subphylum Vertebrata. Present-day vertebrates include amphibians, birds, mammals, fish, and reptiles.
Vertebrates are the most advanced organisms on Earth. The traits that make all of the animals in this section special are their spinal cords, vertebrae, and notochords. It's all about having a series of nerves along your back (dorsal side). If you are an organism, you can't just have the nerves sitting there. You need to give those nerves support and protection. That need brings us to the backbones and a rod of cartilage called the notochord.
The anatomy of a vertebrate includes a stiff rod known as a vertebral column that runs the length of the animal's body. Just above the vertebral column is a tube of nervous tissue known as the spinal cord. Below the vertebral column lies the gastrointestinal tract. The vertebral column consists of a series of vertebrae and intervertebral discs that give the animal both flexibility and structural support.
Vertebrates first appeared about 525 million years ago during the Cambrian Period. The earliest known vertebrate is thought to be Myllokunmingia, an animal that is thought to have had a skull and a skeleton made of cartilage. Today there are approximately 50,000 species of vertebrates which account for about 3% of all known species on our planet. The other 97% of species alive today are invertebrates and belong to animal groups such as sponges, cnidarians, flatworms, molluscs, arthropods, insects, segmented worms, and echinoderms as well as many other lesser-known groups of animals.
The anatomy of a vertebrate includes a stiff rod known as a vertebral column that runs the length of the animal's body. Just above the vertebral column is a tube of nervous tissue known as the spinal cord. Below the vertebral column lies the gastrointestinal tract. The vertebral column consists of a series of vertebrae and intervertebral discs that give the animal both flexibility and structural support.
Vertebrates first appeared about 525 million years ago during the Cambrian Period. The earliest known vertebrate is thought to be Myllokunmingia, an animal that is thought to have had a skull and a skeleton made of cartilage. Today there are approximately 50,000 species of vertebrates which account for about 3% of all known species on our planet. The other 97% of species alive today are invertebrates and belong to animal groups such as sponges, cnidarians, flatworms, molluscs, arthropods, insects, segmented worms, and echinoderms as well as many other lesser-known groups of animals.
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