BIOL 302 Midterm: Biology 302 – Midterm 3.docx

93 views20 pages

Document Summary

How organisms interact: most interactions can be classified by their effect on fitness of the two species involved (+/-, there are limitations to this classification. Doesn"t take into account time (effects may take a long period to play out) We now have increasing evidence that competitive interactions may actually involve more than two species can have a less obvious effect on a third species) Species of snake in south africa by eating eggs of birds. Birds build nests in a plant by weaving fluffy seeds around them, leaving a pungent odor snakes have an aversion to this odor uses fluffy seeds to avoid predation, which also effects the plant. Comes at no cost to one species, but great benefit to another. Both parties benefit fitness effects are positive. Hermit crabs use of garbage from one species to be used by another. Bird nests don"t really effect trees. Only one species benefits, the other is harmed: wolf hunting a rabbit.