2. Mosquitoes

While probably the smallest animal on this list, mosquitoes are truly frightening. Every year they kill about 725,000 people, by transmitting diseases like malaria, dengue fever, yellow fever, and encephalitis. There are more than 3,000 species of mosquitoes, which is more mosquitoes than should exist in the first place.

Mostly, they’re killing people in Sub-Saharan Africa, Asia, and Latin America. But on top of the hundreds of thousands that die, millions more are suffering through these diseases. Mosquitoes really are out to get us. Some scientists are thinking about using gene editing to just get rid of them all, by introducing a mutation that makes females sterile.