Answer:
The best answer to the question, as taking the full question with the option choices from a Brainly question exactly like this one, would be: Over time, the two evolved and were no longer able to mate. This incompatibility was caused by: Allopatric speciation. The salamanders developed different reproductive behaviors, and the species were behaviorally isolated.
Explanation:
Species that share ancestral tyings may become completely different genetically and phenotypically, given certain circumstances and conditions. One such condition is when a species that once shared a common ground, are separated by changes in geography, which will not only separate the species spatially, but will also force each to have to adapt to the new conditions and express different genes that will, at some point, make them two separate species and basically incompatible. This is what happened to these salamander species in California. Since the group divided and one part moved to the east, where they faced a certain type of conditions, and the other to the west, they were separated by space and conditions, and this caused genetic differentiation to the point that now they cannot mate and they behave completely differently, especially regarding reproduction. That is what is known as allopatric speciation and also behavioral isolation.
