Speciation Occurs ____

Question

Speciation occurs ____.  
A) after populations become reproductively isolated
B) when mutations generate observable differences
C) when transitional forms develop between different populations
D) when natural selection pressures reach their maximum
E) randomly as mutations build up in a population

Accepted Answer

Speciation occurs after populations become reproductively isolated, meaning that they can no longer interbreed and produce viable offspring. This can occur through a variety of factors such as geographic isolation, behavioral differences, or genetic incompatibility. The accumulation of mutations may lead to observable differences over time, but it is the reproductive isolation that ultimately leads to the formation of separate species. Transitional forms may exist between populations, but they are not necessarily required for speciation to occur. Natural selection may influence the direction of speciation, but it is not a direct cause. Random mutations may contribute to speciation, but they alone do not lead to reproductive isolation.