Symbiotic Relationship.
Hope this helps.
competition
source: my biology teacher
Starch is present in saliva.
I don't know which food choice you made so I can't explain why you got the results you did.
The coral fossil would be a better estimate of past water depth. This is because most corals inhabit shallow water reefs, less than 150 feet deep. In contrast, pelagic fish may inhabit any open water (pelagic) part of the ocean, with depths ranging anywhere from a couple of hundred feet deep to miles in depth.
