Discussion of Questions
Back to Visualizing Inside the Egg
- Why do you think the yolk of duck eggs is 50% of their egg compared to the
yolk of a songbird, which is only 20%?
Songbirds are inside the egg only about 10-15 days, compared to a whole month for
most duck eggs. Ducklings (and cranes!) must develop their vision, down feathers,
and ability to walk and feed themselves while inside the egg. That takes a lot of
nourishment! Songbirds do a lot of their developing outside the egg while they are
- Why do you think the albumen turns white when an egg is cooked?
The albumen is made up largely of protein. When protein molecules get hot, they start
to fall apart, or become denatured. When this happens, they lose their clear
- Why can't the chick make sounds before it breaks through the egg's inner membrane?
To make sounds, the chick must pass air through its throat and voice box. It
can't do this when it's stuck in a watery sac!
- Why do you think they call the first hole in the shell the star pip?
When the chick is pipping the shell from the inside, and it starts to crack,
the opening is a little bit like the shape of a star.
- Why do you think the scientists at Operation Migration play recordings of
ultralight motors before the Whooping Crane eggs hatch?
Cranes and other baby birds start to learn the sounds of their natural environment
while they are inside the egg, as their hearing develops. Cranes in Operation Migration
need to learn that ultralight motors are safe, so scientists give them an early start.