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Why are bugs attracted to the light?

  1. Jun 24, 2011 #1
    It's such an obvious well known thing but for the life of me I can't think why this would be. Pre-humans the only thing I can think of that would give off light at night are fires and lightning. Neither of which you'd think a bug would want to head towards. What's the evolutionary advantage of such behaviour?
  2. jcsd
  3. Jun 24, 2011 #2
    Moths are not attracted to light. They are nocturnal and use the moon for navigation. They mistake artificial light for moonlight and because of the short distance to the source, their navigation system causes them to spiral in on it.
  4. Jun 25, 2011 #3

    Ivan Seeking

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    Some bugs are sensitive to ultraviolet light reflected by flowers at night. Artificial lights that emit UV rays will also be attractive to these guys. Other bugs are drawn to the heat that incandescent bulbs produce at night. Fireflies are bugs and bulbs all in one. They use their bioluminescence to attract each other.

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