Shell
Bird eggshells are diverse. For example:
- cormorant eggs are rough and chalky
- tinamou eggs are shiny
- duck eggs are oily and waterproof
- cassowary eggs are heavily pitted
Tiny pores in a bird eggshell allow the embryo to breathe. The domestic hen's egg has around 7500 pores.
Read more about this topic: Bird Egg
Famous quotes containing the word shell:
“There are no small number of people in this world who, solitary by nature,
always try to go back into their shell like a hermit crab or a snail.”
—Anton Pavlovich Chekhov (1860–1904)
“We want some coat woven of elastic steel, stout as the first, and limber as the second. We want a ship in these billows we inhabit. An angular, dogmatic house would be rent to chips and splinters, in this storm of many elements. No, it must be tight, and fit to the form of man, to live at all; as a shell is the architecture of a house founded on the sea.”
—Ralph Waldo Emerson (1803–1882)
“I was even more surprised at the power of the waves, exhibited on this shattered fragment, than I had been at the sight of the smaller fragments before. The largest timbers and iron braces were broken superfluously, and I saw that no material could withstand the power of the waves; that iron must go to pieces in such a case, and an iron vessel would be cracked up like an egg- shell on the rocks.”
—Henry David Thoreau (1817–1862)