Ответ:
1) mammals, habit, behavior,vertebrates, invertebrates, influence on the human.
2)1.sometimes we think about...(Present Simple)
2. Who were we in the past?(Past continuous)
3. How did...(Past Simple)
4. Why are we...(Present Continuous)
5. Scientists describe...(Present Simple)
6.They are constantly...(Present Continuous)
7. It is also useful...(Present Simple)
8. This attention to humans ....(Future Simple)