The ecosystem would be harmed, due to the new competition that native phytoplankton-eating organisms would face when the Zebra mussels eat the native specie’s food. This would also affect the phytoplankton population as now that there’s more predators after them, their numbers would decrease faster.
Imperialism in the nineteenth century was primarily focused around Africa, thus resulting in cultural diversity in the continent.
The theory of plate tectonics states that the Earth's solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. Oceanic and continental plates come together, spread apart, and interact at boundaries all over the planet.