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The Ultimate Water Bags as Fly Deterrent Quiz
by Staff
Have you ever noticed clear, water-filled plastic bags hanging in restaurants and wondered just what these were for? Take this quiz and see how a bag of water can keep flies away.

If you see a bag of water hanging in a restaurant, what could be the reason?

  • reduces the temperature
  • saving on water pitchers
  • keeps away flies

Why bother to chase flies away?

  • only a nuisance
  • carry germs
  • ecosystem needs them as prey for birds

What do some advocates of hanging a plastic bag of water insist on adding to the water?

  • burned matches
  • piece of bread
  • flakes of floating tin foil

Why, according to popular theory, would a clear bag of water drive away a fly?

  • The sight of its own magnified reflection scares the fly away.
  • The fly perceives it as a trap and flees.
  • Flies are allergic to water in a plastic bag.

What is the most common reasoning for his method among entomologists?

  • Water filled plastic bags emit a mild resonance that disturbs the fly's hearing.
  • Flies avoid bodies of clear water.
  • The light refraction confuses the fly and so it leaves.

How many simple eyes are there in each complex fly eye?

  • 3,000 to 6,000
  • 500 to 1,000
  • 200 to 300

How do critics classify water bag success stories?

  • triumph of modern technology
  • old wives' tales
  • successful application of fly personality studies

Why could the water bag seem to work?

  • The refracted light distracts the customers and so they don't notice the flies.
  • People are embarrassed to admit a weird theory does not really work.
  • Placebo effect - effect is expected and so perceived.

What did a study using commercial, water-based optical repellants on two egg farms show?

  • no significant effect
  • less flies
  • more flies

What does the study mean for homes or restaurants?

  • direct correlation
  • inconclusive
  • totally irrelevant