How did the zebra gets its stripes? Or the leopard its spots? Besides making cool dinosaur eggs, these balloons provide us with some insight as to how patterns emerge in the prints of animals. Is it possible that the embryonic zebra also had layers to its cells, like in this balloon example, and when it "inflated" (grew up) the layers of cells grew at different rates, giving the striped pattern emergence? I think there is a lot that we can learn though these kinds of analogies in pattern formation. I don't have the knowledge of zebra embryogenesis to back it up, but would love to hear from you if you do!
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Step 1: Materials List
- Food colouring
- General purpose white glue
- Mixing container
- Thumb tacks
- Durabond 90 (I think there would be all kinds of other materials to work just as well, or better. I've used this drywall compound, but I imagine a flour-salt-water solution may work just as well. Think brittle, hard, thin coat of material to fracture when the balloon expands).
Step 2: Apply Glue
- Wash the balloon and dry it to remove
Step 3: Brush Glue
- Brush the glue evenly over the balloon skin
- This glue will help the drywall compound to stick to the skin
Step 4: Hang Balloons Until Tacky
- Hang until they are tacky to touch but not wet. Dry works okay
- I used thumb tacks to pin the balloons to a strip of wood and hang to dry
Step 5: Drywall Compound
Add Drywall compound (or flour-water-salt solution) to a mi
Step 6: Add Water
- Add one part of water for every two parts of drywall compound.
- For four balloons the total weight need not exceed 80 grams
- Mix in food colouring to add to the contrast between the colour of the balloon and the spots.
Step 7: Mix Thouroughly
- Mix until smooth
Step 8: Thickness Test
- When the mixture drips slowly from your finger tip it is ready to be used.
- The material washes off easily from your skin, but be careful! Read all instructions first to make sure you are following safe practice.
- IWear nitrile or latex gloves as a precaution
Step 9: Brush on Compound
- Brush a thin layer of the compound evenly over the balloon
- The thickness of the layer will change the result. Make a few balloons and try different amount o
- Make sure to get high up near the balloon knot, but not over the part where you put your mouth
- Use masking tape to cover the mouth of the balloon if necessary
- Hang to dry - my mixture took about 3 hours to dry.
Step 10: Inflate
- Untie the balloon and blow it up
- Watch as the cracks and fissures work their way over the surface
Step 11: See the Spots!
- That's it! You've made spotted balloons reminiscent of Yoshi's egg.
- Help improve the technique! The spots on mine flake off too easily. Let me know what you come up with!