Vertebrates Animals with an internal skeleton made of bone are called vertebrates. Vertebrates include fish, amphibians, reptiles, birds, mammals, primates, rodents and marsupials. Although vertebrates represent only a very small percentage of all animals, their size and mobility often allow them to dominate their environment. Vertebrates are also interesting because they are easy to find. We coexist with many other vertebrates and are aware of them in our environment. By: Samantha Bunn and Markel Dawson
Vertebrates Vertebrates are among the best studied animal groups…Why? Since, we are vertebrates, we are basically studying ourselves. • They have always been important human resources . • They’re often large, visible, and obvious when being looked for. Vertebrates can be traced back to the Silurian period. All vertebrates belong to the subphylum Vertebrata of the phylum Chordata.
Fish live in water and are the simplest vertebrate group. The three groups of fish are the jawless fish, cartilage fish, and bony fish. Fish are cold blooded, have scales, gills, and a heart with two chambers. Most fish have fins. Fish excrete waste to remove toxic substances like ammonia from their body. Typically a cold blooded organism, fishes are covered with scales. Most of them are found in sea water, while fresh water fishes, and fishes found in streams are also seen in nature. Fishes have two sets of fins that are paired. They also have smaller unpaired fins. They respire with the help of gills. There are a lot of species of fish living in oceans, rivers and other water bodies. It is difficult to categorize the food which forms the diet of these numerous fishes, yet here is an attempt to make you understand more about their feeding habits.
Amphibians live part of their life in water and part on land. They are cold-blooded, have moist skin, no scales, and most young breath with gills and live in the water. They change into adults gradually (metamorphosis) and breathe with lungs. They have three heart chambers, and lay their many eggs in water. Amphibians such as frogs, salamanders, and caecilians, are exothermic animals that metamorphose from a juvenile water-breathing form, either to an adult air-breathing form, or to a paedomorph that retains some juvenile characteristics.
Reptiles live mainly on land and are more complex than fish or amphibians. Reptiles are coldblooded, have dry, scaly skin, most (excluding snakes) have two pairs of legs with five toes on each leg. They breathe with well-developed lungs, have hearts with three chambers, reproduce by laying eggs with tough, protective shells. Reptile babies resemble reptile adults. Reptiles include turtles, lizards, alligators, and snakes. Reptiles are animals in the class Reptilia. They are characterized by breathing air, laying shelled eggs(except of some snakes called vipers that give live birth), and having skin covered in scales and/or scutes.
Birds are vertebrates with feathers and wings, and they are warm-blooded. Birds’ hearts have four chambers. Most birds have wings, build nests in which to lay hard-shelled eggs, and they care for their young until they can find food and survive on their own. Around 10,000 living species makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds (class Aves) are feathered, winged, bipedal, endothermic egg laying, vertebrate animals.
Mammals are the most complex group of animals. They have body coverings of hair or fur, are warm-blooded, have hearts with four chambers, have more complex brains than other animals, more complex body systems. Most mammals give birth to live young, and females have special organs that produce milk to feed their young. Mammals are members of a class of air-breathing vertebrate animals characterized by the possession of hair, three middle ear bones, and mammary glands functional in mothers with young. Most mammals also possess sweat glands and specialised teeth, and the largest group of mammals, the placentals, have a placenta which feeds the offspring during gestation.