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How are animals classified into kingdom, phylum, class, order, family, genus, and species?
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Animal
The fallow deer (Dama dama) has been introduced in many areas ever since the Neolithic Period.
Animals are classified into a hierarchical system known as taxonomy, which organizes organisms based on their presumed natural relationships, structural resemblances, and genetic relatedness.12
Taxonomists place animals into a series of ranks, starting from the broadest category and narrowing down to the specific organism. While there are no explicit, universal features that define every rank, the following hierarchy is generally accepted by zoologists:1
- Kingdom: The highest broad category (e.g., Animalia).13
- Phylum: A major grouping based on body plan (e.g., Chordata).13
- Class: A subdivision of a phylum (e.g., Mammalia).1
- Order: A subdivision of a class (e.g., Primates).1
- Family: A group of related genera (e.g., Hominidae).1
- Genus: A group of closely related species (e.g., Homo).14
- Species: The fundamental unit, identified by a unique binomial name (e.g., Homo sapiens).154
This system is flexible; taxonomists may add intermediate ranks like subphyla or superorders to better reflect evolutionary history. Classification remains subject to revision as new research provides deeper insights into the relationships between organisms.15