Who is in Charge?

I'm not hungry, really. In a group of gobies living in a coral reef, there is one alpha couple, a male and a female. The rest are nonmating females, which have a definite social hierarchy; each is 5 percent to 10 percent smaller than its next higher rival. And when researchers tried to give the smaller fish more food to eat, the gobies would not bite. When a subordinate fish grows closer in size to the next larger fish, a fight ensues, usually ending with the smaller fish's expulsion from the group. And without the protection of the coral, the expelled fish usually are eaten by a predator. Thus, the preferred option is to not eat too much and not make any waves.