BIOL 3170 Lecture Notes - Lecture 12: Monarch Butterfly, Coevolution, Herbivore
Document Summary
Herbivores consume: 10-20% of annual npp in terrestrial ecosystems, 80% of annual npp in aquatic ecosystems, this is why oceans are blue while land is green. They produced more eggs, had better survival, etc: positive effects of plant fertilization on insects could be due to increased plant biomass increased n concentration, decreased defenses, some combination of the above. Plant-stress hypothesis: under stress, soluble n content of plant tissues increases as amino acids are mobilized insect performance improves, especially for phloem-feeders such as aphids, however, herbivore response to host plant stress is often non-linear. Secondary metabolites: che(cid:373)i(cid:272)als that are(cid:374)"t necessary for biochemical activities related to growth or reproduction, unique combinations present in each species, over 10 000 types, they"re the a(cid:374)ti-herbivore allelochemicals discussed in previous pgs. Largest group are n containing compounds called alkaloids. Plant heterogeneity: plants have different concentrations of secondary metabolites in, different seasons, different tissues of the plant (e. g. cellulose, lignin, tannins, different leaves.
