The system of classification in which there are seven hierarchies from kingdom to species was introduced by?

Analyze the question: It asks who introduced the hierarchical classification system with seven ranks, running from kingdom down to species.

Explain the concept: Taxonomy is the science of classifying living organisms. The hierarchical system is made up of ranks, each nested inside the one above it:

Kingdom → Phylum (Division in plants) → Class → Order → Family → Genus → Species

Carolus Linnaeus (Carl von Linné), a Swedish botanist, introduced this system in the 18th century in his work Systema Naturae. He also introduced binomial nomenclature, the two-part naming of organisms (Genus + species, e.g. Homo sapiens).

Check each option:

• A. Felix Dujardin: A French biologist who studied protozoa and described the "sarcode" (protoplasm). He is not linked to classification ranks.
• B. Carolus Linnaeus: Correct. He is the "Father of Taxonomy", who created the hierarchical ranks and binomial naming.
• C. Theodore Schwann: A German physiologist who co-founded cell theory, stating that animals are made of cells.
• D. Charles Darwin: Proposed the theory of evolution by natural selection, not the classification hierarchy.

Answer: Option B, Carolus Linnaeus.

Exam tip: Use the mnemonic "King Philip Came Over For Good Soup" to recall the seven ranks (Kingdom, Phylum, Class, Order, Family, Genus, Species). Whenever you see "classification" or "binomial nomenclature" in JAMB, think Linnaeus. Remember also: Schwann = cell theory, Darwin = evolution.