Answer:
Less reproductive isolation among a population that share similar habitat
Explanation:
Ecological speciation is the brief history of flow barrier to a gene in the population results in ecologically-based divergent selection in the development. This theory is related to the evolution theory of Charles Darwin. It provides the diversity in population on earth. The species occurs by natural selection frequently. The speciation also occurs in two procedure:
The ecological speciation does occur due to the genetic variation in the population.