What type of speciation occurs without any form of isolation?

Sympatric speciation refers to the process in which new species arise from a single ancestral species while inhabiting the same geographical region. This type of speciation occurs without any physical barriers that segregate populations, allowing different groups within the same area to evolve independently due to various mechanisms such as sexual selection, polyploidy, or habitat differentiation.

In sympatric speciation, reproductive isolation can occur through different means, such as behavioral changes or shifts in preferences, which lead to the divergence of species despite existing in the same environment. This unique form of speciation highlights the importance of ecological niches and genetic variability in contributing to the evolution of new species even in the absence of geographic isolation.