Vertebrates

The most advanced living organism on the Earth are vertebrates. Vertebrates are distinguished from non-vertebrates because the structure of the body includes spinal cords, vertebrae, and notochords. Vertebrates have a series of nerves running along their backs, which is protected by the backbones, the spinal column, and cartilage named the notochord.

There are about 65,000 species of vertebrae, but it only makes up about 4% of the animal species on the Earth. The rest of the animals are non-vertebrates or invertebrates. Vertebrates are usually much larger than invertebrates, take up much more space, are more advanced, but also have limitations on the environments where they can live.

Examples of vertebrates are humans, fish, amphibians, reptiles, birds, and other mammals like dogs, cats, elephants, tigers, bears, and many more.

The smallest vertebrate in the world is a tiny frog which grows to just 0.3 inches long, and the largest is the blue whale, which can grow to 400,000 pounds and reach lengths of 100 feet or longer.

Fish are the animals that live in the water, and have gills allowing them to breathe under water. Fish either live in fresh water or salt water. Examples of vertebrates in this category include trout, the great white shark, swordfish, and many more.

Birds are animals with wings and feathers, plus they lay eggs. Nearly all birds can fly, but there are a few that cannot fly, like the penguin and ostrich. Some examples of birds include the bald eagle, robin, flamingo, and many others.

The vertebrate most familiar to humans is the human, which is also a mammal. Mammals are warm-blooded, take care of their young with milk, and have fur or hair on their bodies. Besides humans and many others, mammals also include bears, lions, horses, cats, and dogs.

Cold-blooded vertebrates are amphibians, which begin life living in the water with fish-like gills, but later develop lungs and can live on dry land. Some of the amphibians include frogs, toads, and salamanders.

Finally, reptiles are also vertebrates, which are cold-blooded and they lay eggs, too. Their skins are covered with scales that are hard and dry. Reptiles include snakes, alligators, crocodiles, lizards, and several others.

When an animal is cold-blooded it cannot control its body temperature, and the body's temperature is determined by the air surrounding it. Warm-blooded animals can control their internal body temperature, by sweating, or panting to cool off. In addition, they also have fur or hair to keep them warm.

In summary, vertebrates are the most intelligent species on Earth compared to invertebrates, and are usually much larger. Vertebrates have spinal columns and backbones which contain and protect nerves that then spread throughout the body. There are very few vertebrae compared to invertebrates and make up only about 4% of the animal species on Earth. Vertebrates can be cold-blooded like fish, amphibians, and reptiles, or warm-blooded like birds and mammals. Humans are also vertebrates and are mammals.