1. Understanding The Scientific Method Using Brine Shrimp

2. The Scientific Method Made Simple Ask a question. Ask a question. Gather information about the question. Gather information about the question. Form a hypothesis. Form a hypothesis. Test the hypothesis. Test the hypothesis. Tell others what you found. Tell others what you found.

3. Ask A Question Why do most of the brine shrimp gather or cluster towards one end of the bowl?

4. Gather Information About The Question Brine shrimp live in salty ponds or lakes throughout the world. Brine shrimp live in salty ponds or lakes throughout the world. When conditions are not good, they form an egg that survives drought. When conditions are not good, they form an egg that survives drought. They feed mostly on algae. They feed mostly on algae. Very few predators Very few predators The adult brine shrimp as compound eyes. The adult brine shrimp as compound eyes. The larval stage (nauplius) of the brine shrimp has a simple eyespot. The larval stage (nauplius) of the brine shrimp has a simple eyespot.

5. Great Salt Lake The Great Salt Lake of Utah is a terminal lake. The only way water leaves the lake is through evaporation. The Great Salt Lake of Utah is a terminal lake. The only way water leaves the lake is through evaporation. ut.usgs.gov

6. Stages of the Brine Shrimp Life Cycle Male Female Larva Eggs webs.lander.edu www.aquariumlife.net www.microimaging.ca scicom.ucsc.edu

7. Gather Information Continued It is known that many zooplankton creatures travel to deeper waters by day and come up to the surface at night. It is known that many zooplankton creatures travel to deeper waters by day and come up to the surface at night. Many of these animals have simple eyes for detecting light. Many of these animals have simple eyes for detecting light. The orientation towards or away from light is called, phototaxis. The orientation towards or away from light is called, phototaxis.

8. Form a Hypothesis If zooplankton of the ocean seem to go away from light to avoid predators, what would brine shrimp do if predation is not a problem? If zooplankton of the ocean seem to go away from light to avoid predators, what would brine shrimp do if predation is not a problem? Is light a stimulus that affects their response? Is light a stimulus that affects their response? Would they have the same response as zooplankton of the ocean? Would they have the same response as zooplankton of the ocean?

9. A Possible Hypothesis If I shine a light on one side of the bowl, the brine shrimp will move towards the light.

10. Another Hypothesis If I shine a light on the bowl, the brine shrimp will swim away from the light.

11. Test The Hypothesis Trial#DirectionOrientation + or - Comments 1North+ 2South+ 3East+ 4West+

12. What do the data show?

13. Analyze Your Data and Conclusion The data shows that no matter which direction the light was held, most of the brine shrimp oriented themselves towards the light. The data shows that no matter which direction the light was held, most of the brine shrimp oriented themselves towards the light. The data supports the hypothesis. The brine shrimp did move towards the light. The data supports the hypothesis. The brine shrimp did move towards the light.

14. Tell Others What You Found www.mrg-online.com

15. The Next Step-Why? Some students came to the conclusion that the brine shrimp were attracted to the heat of the flashlight. Some students came to the conclusion that the brine shrimp were attracted to the heat of the flashlight. This could be a new hypothesis to test. This could be a new hypothesis to test. Have the students look at the background information they have collected and see if they can figure out why. Have the students look at the background information they have collected and see if they can figure out why.

16. Possible Reasons Possible Reasons Few predators, no need to hide Few predators, no need to hide Lost of habitat through evaporation Lost of habitat through evaporation Food source is near the surface Food source is near the surface Possible reason-This species has a limited life with no time to migrate up and down in the water column. They must eat and grow to reach the egg stage. That is the only way this species can survive their biggest threat, drought! Possible reason-This species has a limited life with no time to migrate up and down in the water column. They must eat and grow to reach the egg stage. That is the only way this species can survive their biggest threat, drought!