Speciation can occur rapidly between diverging populations, yet the time between speciation events is often more than a million years. Explain this apparent contradiction.

Short Answer

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The length of time required for the divergence of reproduction in newly formed species is long. Speciation occurs only after the reproductive divergence. Therefore, speciation begins rapidly between diverging populations, but the formation of new species takes more than a million years.

Step by step solution

01

Meaning of speciation

When unique characters develop in a group of species, the species of different characters separate from the main population, creating new species from the existing population. This phenomenon is called speciation.

02

Events of speciation

Formation of barrier, entry to a new niche, genetic polymorphism, isolation, and formation of distinct species are speciation events. These events take millions of years to take.

For example, in allotropic speciation, the formation of a barrier (geographical barrier such as the formation of the mountain) alone takes millions of years.

The isolated species undergo different selective pressure than the main population. It leads to divergence. Speciation is one of the evolutionary processes, as the force of evolution, such as natural selection, acts gradually on the isolated species.

03

Role of gene pool on speciation

When a group of species isolates due to barriers, the gene pool remains constant. The significant amount of mutation and interspecific reproduction alter the gene pool of the isolated population.

Reportative divergent traits than the parental population occur only after continuous selective pressure, which takes millions of years to occur.

Thus, the time between speciation events takes millions of years due to the constant gene pool. Reproductive divergence will boost the speciation in a rapidly divergent population.

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Most popular questions from this chapter

Describe two mechanisms that can decrease gene flow in sympatric populations, thereby making sympatric speciation more likely to occur.

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