Eggs are an incredible adaptation that allow birds to stay light and able to fly while their babies are growing. Bird eggs are covered in a shell with lots of tiny holes. These allow air and moisture to pass through. Eggs are also covered in a coating that keeps out bacteria and dust.
To see the parts of an egg and learn about how each part functions, visit: https://www.exploratorium.edu/cooking/eggs/eggcomposition.html
- Materials: an egg or two
- Place the egg in your hand (take off any rings first). Squeeze the egg with even pressure. Does it break?
- Now (over the sink or outdoors) squeeze the egg with just two fingers. Did it break?
What will happen:
- The shape of an egg makes it very strong to even pressure. Even an adult squeezing it can’t break the shell.
- When uneven pressure is put on the thin shell, the egg cracks easily.
- When a bird sits on an egg to incubate it, the pressure is evenly distributed on the shell and the egg can easily support the bird. When a chick is ready to hatch, it pushes on just a small part of the shell with its egg tooth and the shell will crack to allow the bird to hatch.
- An egg
- A drinking glass
- Place the egg in a glass and cover with household vinegar. Wait about 24 hours, pour the vinegar out and replace with fresh vinegar. Wait a full week and then take the egg out.
What will happen:
- The shell is made of calcium carbonate, which dissolves in acetic acid. The vinegar will dissolve the shell, leaving the semipermeable membrane intact. The yolk and white will still be contained in the soft membrane, so it will look like an egg, but will be squishy when touched.
More Experiments & Facts
For even more experiments, and for further explanation of the science behind these experiments, visit: https://www.stevespanglerscience.com/lab/experiments/naked-egg-experiment/?utm_content=exp_rel_exp_main
Learn more about eggs with these books: