1. Symbiosis “Living Together”
Unit C, Chapter 2 Lesson 2
Pgs C46-C51

2. Three Types of Close Relationships
Feeding relationships are not the only ones between organisms.
Many live in a close association called symbiosis.
Symbiosis is a relationship between two organisms of different species. It benefits one or both.
Symbiosis means “living together.”
Behold the cuteness!! Ever hear of the phrase “Keep your friends close and your enemies closer?” Apparently these two were fans of Sun Tzu.

3. Mutualism
Mutualism is a symbiotic relationship in which both organisms benefit.
Mutualism can happen between two plants: legumes have special bacteria that live in them, and convert nitrogen gas into compounds.
Mutualism can also happen between groups of people. Name some examples.
Humans are constantly involved in mutualistic relationships with each other.

4. Examples of Mutualism Honey Guide and Honey Badger
The Clown Fish and Sea Anemone
By leading the badger to the hive, the honey guide gets to eat the larvae, while the badger eats the honey. (Disclaimer!! This is a common example but no proof of this has been found.)
The book calls this commensalism…wrong.
Clownfish get protection from the anemone’s tentacles, and the anemone seems to benefit by fish lured in by the clownfish. Clownfish also apparently scare off butterfly fish (predators).
Lion attacking? Honey badger don’t care.

5. Examples of Mutualism Ants and the Acacia Tree
The Egyptian Plover and Crocodile
Ants and the Acacia Tree
Ants live in the hollow thorns of the acacia tree. They also eat oils produced from the tree.
In return, they clear competing plants away from the tree. They also provide protection. If an unwanted animal intrudes, this happens…
The plover picks rotting meat out from between the teeth for a meal. The crocodile benefits by maintaining dental hygiene.

6. Commensalism
Commensalism is a symbiotic relationship where one organism benefits and the other is not helped or harmed.
Some organisms depend on other living things but don’t affect them.
Birds build their nests in trees for a place to raise their young. This does not help or harm the tree.

7. Examples of Commensalism
Sharks and Remoras
Barnacles and Whales
The remora gets a free ride from the whale shark and also feeds off leftover scraps. The shark is not helped or harmed.
Barnacles attach themselves to whales at an early age. They catch a free ride and visit new feeding grounds. These crustaceans do not harm the whale.

8. Examples of Commensalism
Trees and Orchid Flowers
Egrets and large Herbivores
When large herbivores eat grass, hundreds of bugs run out of their mouths in terror. The Egret lurks outside, waiting to pick them off one by one…..no one is safe.
Orchid’s roots take in nutrients from decaying tree limbs and water that runs down the tree.

9. Parasitism
Parasitism is a symbiotic relationship where one organism benefits and the other is harmed.
The organism that a parasite attaches to is called a “host.”
A successful parasite does not kill its host.
Magnified view of a tick. Notice the really sharp proboscis they stick in you.
Female tick laying thousands of eggs.

10. Examples of Parasitism
Tapeworms and Humans
Magnified view of its head.
Tapeworms attach themselves inside animal intestines and feed off the nutrients from the foods they eat. The host starts to lose weight and become weak.
Tapeworms sold as a diet….no really……people did this….most intelligent species on earth….

11. Examples of Parasitism
Roundworms
Below: Raccoon intestines infected with roundworms.
Roundworms burrow through the muscles of animals causing great pain

12. Still More Examples Leeches Fleas
Fleas bite into the skin to drink the blood.
In this heartwarming scene, Edward the blood sucking parasite latches onto Bella’s head, promising to stay with her forever....until..a new challenger arrives.
I think we’ve almost seen enough parasites….let’s end on a happy note. Maybe some holiday cheer will make things a little nicer.

13. Parasites Have Infected Christmas!!!!
Kissing under the mistletoe is a holiday tradition, but mistletoe is actually a parasitic plant.
It digs it’s roots into the limbs of other trees and bushes and sucks the sap out of them.
Fun Fact:
Mistletoe comes from the Old English Word Misteltan which means “dung and twig”
Maybe we should start a new tradition and kiss under other parasites instead of mistletoe.