Earthquakes have a number of profound effects on local ecosystems, but the most important effect earthquakes have is that they change habitats abruptly. Earthquakes can cause trees to fall, cliffs to crumble and caves to collapse, which can have trickle-down effects throughout the ecosystem.
Usually, earthquakes change habitats in subtle ways. For example, if an earthquake’s epicenter is near a forest, it may knock trees down. When this happens, it allows sunlight to penetrate the canopy, which allows the growth of different types of plants. These new plants support a new population of animals.
Sometimes, earthquakes can create new habitats, ecosystems and ultimately species. For instance, if a portion of the coastline breaks away from the mainland during an earthquake, it will take all of the plants and animals along with it. Over time, the habitat will change in subtle ways, which will necessitate adaptation by the flora and fauna.
Earthquakes can also bring landmasses together, which can have serious consequences. For example, the Indian subcontinent slammed into the Asian continent millions of years ago, due to quake-causing tectonic motion. When this happened, plants and animals were immediately forced to compete with a plethora of new species. Over time, the dominant species overwhelms the subordinate species, and equilibrium is reached.