It has long been known that birds will occasionally build nests in the manes of horses. The only known solution to this problem is to sprinkle baker's yeast in the mane, for, as we all know, yeast is yeast and nest is nest, and never the mane shall tweet.
What is the meaning of the above quote? I am confused by the phrases manes of horses and never the mane shall tweet. An online dictionary says that manes is the plural form, but its singular form, mane, has an entirely different meaning.