Question

The Biological Species Concept was proposed by _________.

• A. Ernst Mayr
• B. Ronald Fisher
• C. Sewall Wright
• D. J. B. S. Haldane

Hint:

Think of the scientist who defined species using reproductive isolation, in his 1942 book on systematics.

Answer 1

The Correct Option is A

The question asks who is credited with the Biological Species Concept, the idea that a species is a group of populations that can interbreed with each other but are reproductively cut off from other such groups. Let's check each name against what they are actually known for.

1. Ernst Mayr: An evolutionary biologist who formally defined species using reproductive isolation as the deciding test, laid out in his influential 1942 work. This is precisely the Biological Species Concept.
2. Ronald Fisher: A key architect of population genetics and the modern synthesis, famous for the fundamental theorem of natural selection, but not for defining species this way.
3. Sewall Wright: Known for genetic drift and the shifting balance theory of evolution in small populations, not for the species concept.
4. J. B. S. Haldane: Known for Haldane's rule and for mathematical work on selection pressure, again a different contribution.

Only Mayr's body of work matches the definition given in the question.

Let's summarize:

• The Biological Species Concept rests on reproductive isolation between populations.
• Fisher, Wright, and Haldane are population genetics pioneers, but the species concept itself belongs to Mayr.

So the Biological Species Concept was proposed by Ernst Mayr.