Extinction of other species will negatively affect human society by affecting multiple things. One thing that may happen is that the ecosystem will fail, and it will eventually become a bare wasteland,n destroying possible recources for humans. As well, if humans have a direct use for them, such as cows for milk, or pics for bacon and ham, those direct recourses will deplete humans recourses, and there may be riots, or the population dwindling because of a lack of recourses. as well, some helpful animals such as plants go extinct, then no oxygen will be exchanged through photosynthesis, and it would cause a lot of pollution,