You Are Studying the Competitive Interactions Between Two Desert Plant

question 61

Essay

You are studying the competitive interactions between two desert plant species, the prickly pear cactus and the ocotillo. During your research, you discover that the ocotillo produces a flower that is preferentially consumed by mule deer, a major desert herbivore. When the deer population is large and has consumed most of the available ocotillo flowers, it eats the flowers of the prickly pear cactus, which reduces the prickly pear's fecundity. Further, you know that the ocotillo and prickly pear compete for water, nutrients, and light. You also discover that the prickly pear secretes a chemical into the soil that inhibits the growth and survival of the ocotillo. For each of these examples of competition between the prickly pear cactus and the ocotillo, name and describe what type of competitive interaction is taking place.