Defensive compounds, quantitative

In order to determine whether the defensive compounds of hybrids of the two Tribolium- species T.freemani and T. castaneum represent simple mixtures of the parental phenotypes, different glandular samples were compared by GC-MS [335]. Concerning the qualitative and quantitative data of the quinones,... 

Peeny (2) has coined the term "apparency" to express the Idea that some plants or plant cooponents are more predictable resources In space and time to potential herbivores. He suggests that such predictable plants are more attractive to specialist herbivores (In evolutionary time) because of their predictability, and thus should employ quantitative defensive compounds which are less susceptible to the evolution of detoxification mechanisms. 

Stamp N (2003) Out of the quagmire of plant defense hypotheses. Q Rev Biol 78 23-55 Steinberg PD (1988) Effects of quantitative and qualitative variation in phenolic compounds on feeding in 3 species of marine invertebrate herbivores. J Exp Mar Biol Ecol 120 221-237 Steinberg PD, de Nys R, Kjelleberg S (2002) Chemical cues for surface colonization. J Chem Ecol 28 1935-1951... 

This model says nothing about what type of compounds a species should use to defend itself, such as high concentrations of polyphenolics or low concentrations of terpenes. The authors suggest that since there is little indication that quantitative/immobile and qualitative/mobile defenses differ in cost, effectiveness, or mode of action, there is little need for the model to predict classes of secondary metabolites. This model could be equally applied to invertebrates by replacing the words seaweed and herbivore with invertebrate and predator. 

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