Force of gravity drives to the process of subduction zones where dense pieces of oceanic crust are pulled downward toward the mantle. We can term subduction as the process by which oceanic crust sinks into the mantle when it collides with continental crust. Subduction destroys oceanic crust by forcing it to the mantle where it melts. Oceanic crust is said to be subducted because they contain more mafic minerals and again it has convergent boundaries. When there is a divergent between continental crust one oceanic crust sinks into the mantle.
Parasites would want to keep their hosts alive because they cannot survive without one. Without a host, parasites will die off, meaning that they wouldn’t want to kill off their hosts, after all, that would kill them too.
