Animals Classified by Biological Characteristics and Mobility
Animals are fundamentally characterized by their need for external energy sources, as they cannot produce their own food and consume other living organisms or their remains. They require oxygen for survival and possess nerve cells that facilitate sensory systems. A defining trait of most animals is their mobility, allowing them to move independently. The classification of animals follows a hierarchical system established by Carolus Linnaeus, which includes seven primary levels: kingdom, phylum, class, order, family, genus, and species. This system helps organize the vast diversity of animal life based on shared biological characteristics. A major division within this classification separates animals into vertebrates and invertebrates. Vertebrates are distinguished by the presence of a backbone or spinal column, encompassing groups such as fish, birds, mammals, reptiles, and amphibians. In contrast, invertebrates lack a backbone and include a wide array of creatures like jellyfish, mollusks, and worms. Mamm...
