What is the name of groups who frequently travel to gather food and hunt animals?

How is an environment able to support different varieties of organisms?

Which mantle is under the crust the upper mantle or the lower mantle i think it's upper let me know if i'm right

Y’all i need answers plss people are saying me and my brother look alike although we’re two different ages. one year apart i’m a girl, btw i’m thinking we could be fraternal twins idk my parents and my friends think we look alike