​Given below are species concepts (Column X) and their descriptions (Column Y):

Column X		Column Y
A.	Typological species concept	i.	Single lineage of ancestor-descendant populations which maintains its identity from other such lineages
B.	Biological species concept	ii.	A species is a set of organisms that resemble one another and is distinct from other sets.
C.	Evolutionary species concept	iii.	Species are groups of interbreeding natural populations that are reproductively isolated from other such groups
D.	Phylogenetic species concept	iv.	A group recognized by its monophyly

Which one of the following options represents all the correct matches?

Correct option is A

​Explanation:

Each species concept defines species based on different criteria, including morphology, reproductive isolation, evolutionary lineage, and phylogenetic relationships.

Correct Matching of Concepts:

1. A - Typological species concept → (ii)
• Based on morphology: A species is a group of organisms that resemble one another and are distinct from others.
• This was an early species concept, used before genetics and evolutionary biology.
2. B - Biological species concept → (iii)
• Defined by Ernst Mayr (1942): A species consists of interbreeding populations that are reproductively isolated from others.
• This concept applies well to sexually reproducing organisms but not to asexual species.
3. C - Evolutionary species concept → (i)
• Defined by Simpson (1961): A species is a single lineage of ancestor-descendant populations that maintains its identity over time.
• Focuses on evolutionary history and continuity.
4. D - Phylogenetic species concept → (iv)
• Based on monophyly: A species is a smallest diagnosable monophyletic group.
• Used in cladistics and molecular phylogenetics.

Information Booster:

• Typological Concept: Used in classical taxonomy, relies on fixed essential traits.
• Biological Concept: Most widely accepted but fails for asexual organisms and fossils.
• Evolutionary Concept: Bridges biology and paleontology, useful for extinct species.
• Phylogenetic Concept: Used in molecular phylogenetics, recognizes smallest evolutionary units.