ABSTRACT
In this chapter, we treat two apparently unrelated topics: evolution and invertebrate immune systems. They are, in fact, closely related. Invertebrate immunity evolved with the organisms; it was required to Ÿght the Red Queen battles for survivalof the Ÿttest against other infective and/or competing species. One dimensionof an invertebrate animal’s Ÿtness is seen to be arobust, competent immune system.
