What are hybrid zones, and why can they be viewed as “natural laboratories” in which to study speciation?

The biological species concept describes that the population comprises members, and such members are called species. Species of a population potentially and naturally interbreed.

The species of a population is not determined by their appearance but only by their interbreeding. However, the appearance of the species assists in identifying the organisms.

The species with an incomplete reproductive barrier breed and give rise to new species which possess the traits of both the parental species. The region or habitat in which two different population mates is called a hybrid zone.

The organisms formed from this process are called hybrid species. Hybrid forms often show decreased fitness than their parental population. A hybrid zone is typically observed in a location where interbreeding species inhabit. The species without reproductive barriers mate in this place.

The evolution of reproductive isolation is revealed by observing the hybrid zones of the different populations.During mating and sexual selection in two diverse populations, the behavior of species is directly visible in the hybrid zone.

The effect of environmental condition on a hybrid zone, an act of natural selection on hybrids, and the factors that cause the reinforcement of reproductive barriers is known through the hybrid zones.