Your respiratory muscles contract each time you exhale.
truefalse

This is the diveristy of ecosystems natural communites and habits it is the variety of ways that species interact with each other and their environment

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.

Which of the following explains why a tree is often used as a model to represent the principle of common descent