Lectures on species interactions and competition

Three types of competitive interactions
1. Direct interference competition: Species actually confront each
other (e.g., strangler figs, allelopathy in plants).
2. Exploitation competition: Species have a negative impact on each
other through competition for resources (e.g. competition for
light, water, or nutrients).
3. Apparent competition: Species have a net negative impact on one
another, but this is indirectly mediated through a third species.
(e.g., if two species are affected by a herbivore, increasing plant
species A may increase the herbivore population, with a greater
net negative effect on species B. Thus, increasing A may lead to a
decline in B with no direct interaction between them.