Sherlock Holmes and Dr. Watson decide to go on a camping trip. After dinner and a bottle of wine, they lay down for the night, and go to sleep. Some hours later, Holmes awoke and nudged his faithful friend.

Sherlok: "Watson, look up at the sky and tell me what you see."

Watson: "I see millions of stars."

Sherlok: "What does that tell you?"

Watson (pondered for a minute):

…

Watson: Astronomically, there are millions of galaxies and potentially billions of planets. Astrologically, Saturn is in Leo. Chronologically, it is approximately a quarter past three. Theologically, God is all powerful, and we are small and insignificant. Meteorologically, we will have a beautiful day tomorrow. What does it tell you, Holmes?

Sherlock was silent for a minute, then spoke:

…

Sherlock: "Watson, you idiot. Someone has stolen our tent!"

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• Gliwicz MZ (1986) Predation and the evolution of vertical migration in zooplankton. Nature 320:746–748