All the following are characteristics of the blue crab EXCEPT A. It has no natural predators.
B. Blue crabs often feed on each other.
C. It can adapt to varying levels of sanity.
D. It migrates to cooler temperatures as it ages.

Adigestive system that is a series of tubes beginning at the mouth and ending at the anus is a digestive system.

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

What are two ways that harvesting algae from the ocean may benefit human society? how might the harvest of algae negatively impact the ocean communities where that algae grows? how could this be prevented?