BIOLUMINESCENCE

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BIOLUMINESCENCE
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Aequorea victoria
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Melanostomias bartonbeani
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Bargmannia sp.
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Beroe sp.
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Substrates and Enzymes

• Luciferin
• General term
• Luciferase
• Present in diverse taxa
• Oxygenase
• Exaptation

Bacterial luciferin
Vargulin
Coelenterazine
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Examples of fish
Bacterial luciferin
Vargulin
Neuronal control
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Chemical luminescence
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INTERSPECIFIC COMMUNICATION

• PREDATOR AVOIDANCE
• PREY ATTRACTION
• BURGLAR ALARM HYPOTHESIS

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PREDATOR AVOIDANCE
Acanthephyra purpurea and Gonostoma elegatum
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PREDATOR AVOIDANCE
Counter illumination
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PREY ATTRACTION
Melanocetus sp.
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SIGNAL DETECTION THEORY
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BURGLAR ALARM HYPOTHESIS
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SIGNAL DETECTION THEORY
MANIPULATION/ DECEIT
SPITE
TRUE COMMUNICATION
EAVESDROPPING
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FLASH LIGHT FISH

• Nocturnal Predator
• Bacterial light organ
• lluminates prey
• functions as bait

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• 10 billion bacteria / .035 fluid oz
• Light emitted travels over 30 m
• Brightest light produced by any living organism

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POTENTIALLY COSTLY ADAPTATION

• Five genera and six species worldwide
• DIFFERENT STRATEGIES
• Two species raise skin flaps to control emission
• Two species lack skin flaps use organ rotation
• Two species use both skin flaps and organ
  rotation

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Skin flap down, light organ exposed
Skin flap up, light organ covered
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Do different species differ in their ability to
manipulate/ deceive predators???
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EXPERIMENTAL DESIGN

• Large scale aquaria experiments
• Two treatments for each species
• -control mechanism intact
• -control mechanism removed
• Common, visually stimulated, nocturnal reef
  predator

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EXPECTED RESULTS
PREDATOR - PREDATOR
0 100
0 100
0 100
CONTROL
INTERMEDIATE
BOTH ROTATE SKIN - -
-
LOW
CONTROL
CONTROL
HIGH
SURVIVABILITY
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SIGNAL DETECTION THEORY
MANIPULATION/ DECEIT
SPITE
TRUE COMMUNICATION
EAVESDROPPING
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Intraspecific Communication

• Schooling
• Communication
• Mating

Oneiroides sp.
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Is bioluminescence used for mate selection?
Euprymna scolopes
Vibrio fischeri
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Light organ of E. scolopes

• silver colored reflector
• shutter mechanism
• transparent lens
• yellow filter

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Influence on mate selection?

• Light organ quality may signify fitness
  (survivorship)
• Under sexual selection?
• Hypothesis Variation in light organ
  characteristics will influence mate selection in
  E. scolopes

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Experimental design part 1

• Test for variation in light organ
  characteristics
• size and shape of light organ
• size and shape of reflector tissue
• Wavelength of light emitted
• Intensity of light emitted

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Experimental design part 2

• Capture male and female E. scolopes
• Measure wavelength (l) intensity (I)
• Assign males to categories of l I
• Group 1 female w/ multiple males that differ in
  l I (control for other features)
• Record mating pairs
• Repeat using other females

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Expected results

• There will be a statistically significant
  correlation between mating events and category
  of l and/or I .

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Malacosteus niger
The ultimate eavesdropper
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Conversion of light
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Physiology experiment

• How is light signal perceived?
• Conversion of wavelength not perfect
• Excites visual pigments
• Different detection than naturally emitted blue
  light?
• Monitor nerve impulse
• Sensory processing centers
• differences in activity?