High human populations have had a negative effect on D). Biodiversity. The reason why this would be your answer is because the more the human population increases, the less amount of animal life there is. Biodiversity is the variety of species in a area or ecosystem, and the increase in human population has been effecting the diversity in this world. Because the human population is increases, there has been a big difference in animal life,. and animal life has been decreasing as some species are becoming extinct. This has a negative effect on biodiversity because there will not be that much diversity in this world because of the human population, there are more humans now than ever.