The right answer is option d as its absence would impact many organisms in the ecosystem.
Keystone species are crucial for the ecosystem's health. If such a species were to disappear from an ecosystem, it would disrupt the ecosystem's functioning, leading to significant consequences. Therefore, keystone species are vital for the ecosystem's survival.
The ideal choice is a video showcasing penguin species that exhibit distinct mating dances. Reproductive isolation refers to the unsuccessful interbreeding among animals of closely related species due to various differences that could be ecological, behavioral, psychological, or genetic. In the scenario mentioned, the variation in the mating dances among penguin species prevents them from connecting and reproducing. This situation exemplifies reproductive isolation. Factors contributing to reproductive isolation include differences in mating behaviors, sterility, or environmental obstacles that ultimately lead to the evolutionary divergence into separate species. Nonetheless, while reproductive isolation is necessary, it is not enough on its own; internal obstacles to gene flow are also needed for speciation to occur.
Response:
The introduced species, lacking natural predators in the new environment, can reproduce excessively and deplete resources needed by native species, potentially leading them to extinction.
Clarification:
