Triops Tale

by Jordi

Triops are primeval shrimp that live in fresh water ponds they where alive at the same time as the dinosaurs. They can grow to be two inches long, and they live about 70 days. They double in size every day so they are full-grown before the pond dries out. What is really neat about triops is that their eggs can last for years and still hatch even if they freeze during winter, or roast in the summer! So we decided to see if they could survive in really hot temperatures so we bought some triops eggs and cooked them.

When I heard that we would have to do a science fair project, I was not sure what to do until I remembered a movie I had seen about primeval shrimp, and it had said that their eggs would hatch even after they were immersed in boiling water. Since it didn't say which shrimp were tested I decided to test triops for my science fair project. So we decided to go from not cooked to 240°F by going up by 20°F.

We soon ran in to trouble when noticed that our oven didn't go lower than 170°F. So we made an oven out of cardboard and Styrofoam with an upside-down steam iron in the bottom.
Inside of Iron Oven
Iron Oven

Now we planned to cook eggs at 120-160°F in the iron oven, and at 180-240°F in the oven.

We prepared the eggs by wrapping them in small pieces of aluminum foil to make thin flat packets about half an inch square.

Oven Setup To set up the oven we put a cookie sheet on the middle rack to act like a heat shield so the heat rays from the red hot elements at the bottom of the oven wouldn't heat up the small eggs to quickly. We put a pizza pan on the top rack in the middle of the oven to even out the heat for the eggs. We placed the triops eggs in the middle of the pizza pan after heating the oven to the proper temperature, and left them there for one hour.

The thermometer that we used in the iron oven is a dial with an eight-inch long tube with a diameter of 1/8 inch sticking out the back. We placed the small end of the thermometer in one of the steam holes near the center of the bottom of the iron and the dial is taped to the top of the oven.

We controlled the temperature of the iron oven by plugging in the iron for five to six seconds every three to five minutes as necessary. First we heated the iron to the temperature. Then we put the eggs in the center of the bottom of the iron next to the end of the thermometer for one hour.

Triops hatchery To hatch the triops and grow them we filed eight jars whit river water and placed them in a tub of water insulated with a sleeping bag. We arranged the eight jars in a circle in the tub with a 50 watt aquarium heater in the middle so that when the heater heated up the water around the jars all the jars where the same temperature. We put a low heat fluorescent lamp over the jars in the middle so thay all get got the same amount of light.

The following table shows which eggs hatched and which didn't:
Temperature°F Hatched Oven Iron Oven
N/A Yes N/A N/A
120 Yes X
140 No X
160 No X
180 Yes X
200 Only one X
220 No X
240 No X

How can we explain that the eggs cooked at 180°F hatched but those cooked at 140 and 160°F didn't?

  1. Did the eggs on the iron get hotter than we measured?
  2. Were the eggs cooked at 140 and 160°F duds before we cooked them?
  3. Was the oven temperature lower than we measured?

How can we answer these questions?

The iron oven might have got to hot because the thermometer was to slow, and the thermometer probably measures an inch back from the tip so it didn't get the reading of the bottom of the iron.

If the eggs were bad we could have this problem fixed by mixing the eight sets of eggs we bought all together then separating them in to eight sets again.

We didn't have an idea what the oven was doing or if the oven thermometer was right or not.

We got a new thermometer that is a thermocouple. A thermocouple is two different metals welded together at two ends. When the two ends are different temperatures it produces a voltage. It is mounted in the tip of a thin hypodermic needle so it has a fast reaction time. We also got a controller that reads the voltage from the thermocouple and turns that into temperature, and it sends that information to the computer. Then the computer records it and makes a line graph. The controller also has a receptacle, which it can turn on and of rapidly to control a heater.

We used the new thermometer to answer questions 1 and 3 above. We investigated what happened in the oven and the iron oven by reenacting those parts of the experiment. The data is shown in the following charts.

This is a temperature lay out from the iron oven. As you can see it Is quite unreliable it was so post to be at 140°F. Iron oven temperature at 140 degrees F

This is the oven set up for 180°F

Oven temperature at 180 degrees F

We made a new oven out of a cardboard box, a light bulb, two small pieces of aluminum bolted together with spaces between them for the eggs and the thermocouple. We built it by making a box with the light bulb in the middle of the inside so the top of the light bulb is even the top of the box. The aluminum fits in a T shaped hole in the top of the box so it is resting on the top of the bulb. The end of the thermometer is placed in a hole in the side of the aluminum through the stem of the T shaped hole. The aluminum and the thermometer are covered by Styrofoam attached to a piece of cardboard with cutouts for the thermometer and the aluminum, and to allow the packet of eggs to be placed in a slot in the aluminum. The light bulb and the aluminum are pressed together to get good heat conduction by placing a weighted can on top of the Styrofoam. We plugged the light bulb in to the receptacle in the back of the controller.
Inside of bulb oven Egg slot in aluminum part of bulb oven
Thermocouple hole in aluminum part of bulb oven How eggs inserted in bulb oven
Bulb oven with cover Bulb oven
Bulb oven heating up Bulb oven off at set point
Bulb oven on at set point

With this box our controller was able to keep the aluminum with in one °F of a constant temperature. The only problem with the new oven is that you have to heat it to the right temperature before you put the eggs in because it over shoots by about 5°F in the beginning.

We ran our experiment again using our new egg heater. We used the information from our previous experiment to narrow the temperature range to175-210°F in eight steps of 5°F. We shuffled the eggs as described above.

Temperature°F Hatched
175 At least 5
180 At least 5
185 Only one
190 None
195 None
200 None
205 None
210 None
We checked our thermometer on boiling water and ice water. At our altitude at normal pressure, water boils very near 200°F. We think the temperatures we measured are less than 5°F from the real temperature.

We think that it would be neat to repeat the experiment several times to be more sure of our results. We also think it would be neat to see if the triops eggs could survive higher temperatures for shorter times.

If we could harvest the triops eggs that survived we might be able to make them evolve to survive hotter temperatures. (I think that will be way more triops than I want to grow.)

Oven Setup this is a picture of our new thermometer set up the computer is taking data from the temperature controller (middle) witch is reading data from the thermo copal(the metal thing in the pot)