Allomones I chemical defense by animals

The bonnacon [bison]. . emits a fart with the contents of his large intestine which covers three acres, any tree that it reaches catches fire and its pursuers are driven off with the noxious excrement.. 

ANON (c. 1150)Be5rw (transl.anded.T.H.White)NewYork Putnam. 

Allomones are interspecific semiochemicals that primarily benefit the sender. Animals as well as plants defend themselves chemically against predators. Myriads of ways to deter predation have evolved. Many chemicals have more than one function, being aimed not only at predators but also at parasites, prey, or conspecific competitors. As common denominator of allomones we assume that the inclusive fitness of the sender - rather than the receiver - is enhanced. Chapter 10 deals with defenses by animals, and Chapter 11 with plant defenses against herbivores. 

Among fish we find some of the most potent toxins in animals. We dis-tinguish passivelj toxic fish from actively toxic fish. The former simply have toxins in their tissues, typically taken from some other source such as their diet. The latter produce the poison and have evolved apparatus to discharge, deliver, or inj ect the 

FIGURE 10.1 Ciguatoxin. It passes through food chain from dinoflagellates to herbivorous and carnivorous fish, and humans. 

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