Answer:
The comb jelly (Mnemiopsis leidyi) became invasive in the Black Sea in the early 1980s, likely due to its introduction via ballast water from ships from the east coast of the United States. Its rapid spread and high reproductive rate allowed it to become the dominant species in the Black Sea, out-competing native species for food and resources. It has since spread to other parts of the world, including the Mediterranean Sea and the Caspian Sea.
Step-by-step explanation: