1. The Case of the Missing Zooxanthellae
Who killed Seymour Coral?

2. Clues to Students…
As you solve this mystery, please take notes on the important clues.
You will know an important clue because it will be bold and underlined.
You will be expected to have the bold and underlined information in your notes when this mystery is concluded.
Please give students the Pre- and Post-Survey at this time.

3. Now, let’s get familiar with the concept so the culprit doesn’t get away with it!... We’ve got be smarter than the bad guys!

4. Marine Mystery – a watery who-dunnit!
Center for Microbial Oceanography: Research and Education
OT CROSS! – Police Line – DO
Image:
Police Line – DO NOT CROSS! – Poli 4

5. 70% of the earth’s surface is covered by ocean!
Image: 5

6. The rainforests of the sea
Coral reefs only make up 1% of the Earth’s surface, but they are home to over 25% of all marine life!
What are some things that live in a coral reef habitat?
Before we talk about things that affect coral reefs, what the heck is a coral in the first place?!
Image: unknown source 6

7. The mutualistic relationship between coral and zooxanthellae
Zooxanthella are single-celled, plant-like algae that live in the tissues of the coral
These cells provide food for the coral in exchange for a place to live
Have kids repeat zooxanthellae.
Photo: 7

8. Photosynthesis: Helping plants grow for over 2.3 billion years!
Plants, phytoplankton and algae in the oceans need the same ingredients to live and grow as plants on land:
Carbon dioxide + water
Carbon
dioxide
Water
Organic
carbon
Oxygen
food + oxygen
How much food do the cells living inside of corals provide? Up to 98% of the coral’s diet! In fact, corals with zooxanthellae grow 3 times faster than those without them! So, keeping zooxanthellae happy is a top priority for corals. Unfortunately, that isn’t always an easy task.
Image 1:
Image 2: Seija Hallförs,
Image 3: unknown source 8

9. Did you know that 70% of the Earth’s oxygen is produced by marine plants, plankton and algae? Wow!
How much food do the cells living inside of corals provide? Up to 98% of the coral’s diet! In fact, corals with zooxanthellae grow 3 times faster than those without them! So, keeping zooxanthellae happy is a top priority for corals. Unfortunately, that isn’t always an easy task.
Image 1:
Image 2: Seija Hallförs,
Image 3: unknown source 9

10. Coral bleaching: Life in the lurch
Coral bleaching is when corals turn white because they lose their zooxanthellae.
Caused by:
 increased water temperature
 changes in sunlight/UV radiation
 sedimentation
 chemical pollution
Who has heard of coral bleaching? Coral reefs are one of the most fragile ecosystems on earth.
They can bleach, or lose their symbiotic algae, when put under stress.
The coral can replace their zooxanthellae and recover if the environmental stress doesn’t last long. But if any of these conditions persist, the coral will die. Let’s look at each of these threats.
Image 1: Ove Hoegh-Guldberg, Centre for Marine Studies, The University of Queensland
Image 2: Dr Ray Berkelmans (AIMS)
Image 3: Photo by J. Kenyon, reproduced from Friedlander et al 10

11. Global warming
Car analogy – what happens when you sit in the car with windows rolled up?
Sunlight comes in through the windows and heat gets trapped in the car. Carbon dioxide acts like the window in the car on a sunny day.
Image 1: unknown source
Image 2: unknown source
Image 3:
Burning fossil fuels, like coal and gas, increases the amount of carbon dioxide (CO2) in the air and oceans.
CO2 keeps solar heat trapped near the Earth’s surface, and could cause land and oceans to warm up.
Zooxanthellae can’t photosynthesize in very warm water and they abandon the coral. 11

12. Examples of Coral damage due to Global Warming

13. Sedimentation
Human land use (for farms, mines, or buildings) loosens soil and increases erosion.
Dirt gets washed into the ocean where it can block out light and even smother corals.
This picture shows the coast of west Maui. What can you see?
When it rains, dirt gets washed into rivers and streams, where it is carried to the ocean.
If the zooxanthellae don’t get enough light, they may abandon the corals.
Image: 13

14. Examples of Coral Damage due to Sedimentation

15. Nutrients and algal blooms
Much like dirt, fertilizers that are used to grow food can also get washed off the land and into the ocean.
These nutrients can cause algal cells to reproduce rapidly, and they can block out light too.
Image:
Red colored algae 15

16. Examples of Coral Damage due to Algal Bloom

17. Industrial pollution
Factories that build anything from cars to carpets create waste.
This type of pollution can either poison the coral or keep it from being able to eat and reproduce effectively.
Image 1: unknown source
Image 2: unknown source
Image 3: 17

18. Examples of Coral Damage due to Industrial Plant

19. Based on our background knowledge… Who are our possible suspects in the case?

20. Pause for skits.

21. What we know so far… Seymour Coral was found dead.
His zooxanthellae were missing and are still missing.
Mr. Coral’s zooxanthellae are single-celled SYMBIOTIC ALGAE that live inside the coral. In exchange for a place to live, the zooxanthellae provide up to 98% of the coral’s diet.
Without his zooxanthellae, Mr. Coral could have STARVED to death!!
Students should take notes. If they have their netbooks, they can type notes straight into a Word document.

22. Pause to look at evidence and discuss who you think is guilty.

23. So who is the killer? Did they act alone?
Write your deposition.
Claim – Who did it?
Evidence – What clues led to your claim?
Reasoning – What is the reason that these clues support your claim?