High quantities of nutrients in water from industrial crop fertilizers and animal waste cause excessive aquatic plant growth — a process known as “eutrophication,” which, in turn, causes “hypoxia,” or water that is low in oxygen. Harmful algal blooms (or HABs) occur when aquatic algae grow rapidly out of control.
Idk the options but it could be genetic variation
Animals defend their territories because it’s kinda a instinct and they want to be in charge
Not sure but i think cohesion forces
