Geographical isolation is associated with
a. allopatric speciation
b. sympatric speciation
c. clones
d. prides
The correct answer and explanation is :
The correct answer is a. allopatric speciation.
Explanation:
Geographical isolation is a key factor that leads to allopatric speciation, a process by which new species are formed when populations of a species become geographically separated. The separation can occur due to physical barriers such as mountain ranges, rivers, oceans, or even human activity. Once isolated, these populations can no longer interbreed and exchange genetic material, leading to differences in their gene pools over time.
In allopatric speciation, the isolated populations experience different environmental conditions and selective pressures, which can lead to genetic divergence. This divergence occurs through processes such as mutation, natural selection, and genetic drift. Over many generations, the accumulated genetic differences can become so significant that even if the geographical barrier is removed, the populations are no longer capable of interbreeding and producing fertile offspring. At this point, they are considered separate species.
A classic example of allopatric speciation is the evolution of the finches on the Galápagos Islands. These finches, originally part of a single population, were geographically isolated on different islands. Over time, they adapted to different ecological niches on each island, resulting in the emergence of multiple distinct species of finches.
In contrast, sympatric speciation (answer choice b) occurs when new species evolve within the same geographic area, often due to ecological or behavioral differences that reduce gene flow between populations. This does not involve geographical isolation.
Clones (answer choice c) refer to organisms that are genetically identical, typically produced through asexual reproduction, and are not related to speciation processes.
Prides (answer choice d) refers to a social group of lions, and it is unrelated to the concept of speciation. Therefore, the correct answer remains a. allopatric speciation.