One day the small animals sent emissaries to the eagle.
“The snake has been terrifying us all,” they said (from a safe distance away). “He comes without warning, steals our young, and eats them. We lose ten percent of them a year to him. We live in constant fear, never knowing when he might strike again. We believe that you could rid us of this menace.”
“And so I shall,” said the eagle. “But you do realize there will be a price to be paid…?”
“We don’t care,” said the small animals. “We must be rid of this threat, so we can live normal lives.”
So the eagle found the snake, and they fought a tremendous fight, which the eagle won. The small animals came out to cheer him (from a safe distance away).
“Thank you for your appreciation,” said the eagle, his beak still bloody. “Now let’s talk about the price.
“I will require fifteen percent of your offspring each year. Decide among yourselves how that will be done, but deliver them to me without fail, on a regular schedule. Do this, and I will always keep the snakes away.”
The small animals were astonished. “How is this any improvement from before?” they asked, incredulously.
“Simple,” replied the eagle. “You will no longer need to live in fear of the unexpected.”
The moral is: Predators are predators – but some are more systematic than others.