You can mix them by the same thing of generic
Draining the oceans would show features such as mid-ocean ridges. These features would look like an extensive mountain range running down the spine of the ocean floor. This region marks the area where two oceanic tectonic plates are being pushed apart. Closer to land or the continents would be a gentle shelf that gradually deepens as one moves away from the coastline. This relatively gentle plain would then make a steep drop off down to an extensive plain stretching towards ocean ridges. The ocean floor also supports lone mountain structures, canyons and chasms.
Answer:
The sun
Explanation:
The is because the sun is the souce of energy
1 hormones
2 external stimuli
The main food sources of the birds( the plentiful recourses within the environment occupied by the species)
