October 26 & 27

* Definition: a close and often long-term interaction between two different biological species.

* A relationship between individuals of different species where both individuals benefit.

* The anemone provides protection for the hermit crab and the hermit crab gives the anemone more access to different foods.

* Cows have a variety of bacteria in their bodies. Many of the bacteria live in their digestive tracts and help them digest the grasses they eat. The bacteria receive a place to live and a plentiful food supply.

* The oxpecker eats off insects and receives a meal and the impala has insect pests removed from them.

* Bees fly from flower to flower gathering nectar, which they make into food, benefiting the bees. When they land in a flower, the bees get some pollen on their hairy bodies, and when they land in the next flower, some of the pollen from the first one rubs off, pollinating* the plant. This benefits the plants. In this mutualistic relationship, the bees get to eat, and the flowering plants get to reproduce.

* A relationship between individuals of different species where one individual benefits and the other is harmed.

* In the southeastern U.S., kudzu was imported from Japan to help control erosion. Since then, kudzu has grown out of control, spreading across the region, climbing up every tree in its path. By climbing up the trees, kudzu blocks sunlight from these trees, as well as other plants.

* Mistletoe plants grow on a wide range of host trees; they commonly reduce their growth and a large plant stunts and commonly kills the distal portion of branch it grows on. A heavy infestation may kill the entire host plant.

* Flea has a place to eat and live and the cat is harmed.

* A relationship where one organism benefits while the other is unaffected.

* Vultures eat the scraps that the lions leave behind. The vultures gain food from the lion, but nothing happens to the lion itself.

* In these relationships, one organism is harmed while the other is unaffected.

* The trees secrete juglone which inhibit growth in surrounding trees, shrubs, grass, et cetera. There is no benefit to the black walnut tree in doing this.