Competition occurs between species when

they fight for mates

their niche is destroyed

they try to share the same niche

a new niche becomes available

The correct answer for the fill in the blank is- They try to share the same niche.

According to competitive exclusion principle, two species when present in the same area, try to compete for the same limiting resource like food. The species having better advantageous trait over the other survive and exclude the other one. In other words, the second species is either eliminated or shifts to some other niche.

This principle is also called Gause's principle.

Thus, competition occurs between two species when they try to share the same niche.

the water is warmed up by the sun and then it evaporates into the atmosphere. the sunlight warms the water by its heat. water is then cooled down and condensation takes place. the water then finally returns back to the earth by the process of precipitation in the form of rain or ice.

explanation:

voluntary muscles are controlled by the cerebellum.