What is a close relationship between two organisms that live together called ?

Air pollution is only caused by human activity, select the best answer from the choices provided ot of true or false

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.

What is used to keep track of the gamates and possible offsprings combination