The term "allopatric speciation" is best defined as:

• A. the rapid evolution of many species from a single ancestor in a short period
• B. the merging of two previously distinct species into one
• C. the formation of new species due to geographic isolation of populations
• D. the formation of new species within the same geographic area without physical barriers

Answer: (C)

Verified step by step guidance

1. Understand the term 'allopatric speciation': It refers to the process of forming new species when populations of the same species become geographically isolated from each other, preventing gene flow between them.
2. Recognize the key factor in allopatric speciation: Geographic isolation is the primary driver. This isolation can occur due to physical barriers such as mountains, rivers, or distance.
3. Compare with other forms of speciation: For example, sympatric speciation occurs without geographic isolation, often due to ecological or behavioral differences within the same area.
4. Eliminate incorrect options: The rapid evolution of many species from a single ancestor (adaptive radiation) and the merging of two species into one (hybridization or fusion) are unrelated to allopatric speciation.
5. Conclude that the correct definition of allopatric speciation is 'the formation of new species due to geographic isolation of populations.'