What term describes speciation that occurs within parent populations?

Sympatric speciation is the term that describes the process of speciation occurring within a parent population, without physical barriers separating groups. This type of speciation occurs when members of a species become reproductively isolated while living in the same geographic area. Factors that can contribute to sympatric speciation include polyploidy (especially in plants), sexual selection, and variations in ecological niches within a shared environment.

In environments where different resources or habitats are available, individuals may adapt to specific conditions or preferences, leading to reproductive isolation over time despite being in close proximity. This contrasts with other types of speciation, such as allopatric speciation, which involves geographic separation leading to the formation of new species, or parapatric speciation, which occurs when populations are adjacent but not fully separated. Understanding these processes is crucial for grasping how biodiversity arises and evolves within ecosystems.