BIOLUMINESCENCE OF DEEP SEA ORGANISMS Lauren Arneson Tim

BIOLUMINESCENCE OF DEEP SEA ORGANISMS Lauren Arneson, Tim Carter, Julie Kaye

QUESTIONS • Why bioluminescence evolved? • How many different ways are bioluminescence produced? • What is its adaptive significance? • How many times it has evolved?

BIOLUMINESCENCE • Production and emission of light • Produce luciferin and luciferase • Most produce green or blue light

TYPES OF BIOLUMINESCENCE • Bacterial • Extracellular -Happens outside the cell • Intracellular -stay inside the cell

ADAPTIVE SIGNIFICANCE • Bioluminescence has the potential to play a major role in influencing population dynamics in light limited environments • Bioluminescence is a widespread phenomenon in the marine world with over 20 functions advanced • Some organisms use luminescence to lure prey • Others employ luminescence to blind, startle, or decoy potential predators, or to expose them to secondary predation

ADAPTIVE SIGNIFICANCE • The study of marine visual systems is important to understanding the adaptive significance of bioluminescence as the optical properties of the water environment greatly influence the evolution of both signal generation (bioluminescence) and signal detection (vision). • For luminescence to have ecological significance it must be perceived. • Many bioluminescent organisms possess such primitive visual systems that their emissions have evolved for detection by more visually sensitive species. • Luminescence plays a critical role in structuring population dynamics in low light intensity environments. Although a number of studies have been conducted on near shore luminescent fishes, few have been able to monitor luminescent interactions. • The midshipman, Porichthys notatus, is an excellent for studying luminescence interactions.

ALLEN MENSINGER • 2 cultures of dinoflagellate in two different cycles • The non-luminescent mysids were placed in experimental aquaria containing dinoflagellate in either their luminescent phase or nonluminescent phase • Juvenile midshipman fish, P. notatus (primary predator), were then added to the dinoflagellate, P. fusiformis, and mysid, H. costata, aquaria • Predator prey interactions were monitored with DAGE MTI image intensifying camera, fitted with a blue-green glass filter that absorbed wave-lengths longer than 650 nm, and infrared (IR) video cameras. • Encounters were analyzed frame by frame

• The cameras allowed simultaneous viewing of predator prey interactions and the luminescence that took place • Mysid movements stimulated dinoflagellate luminescence which in turn caused the mysids to illuminate • Mysid movement excited a number of flashes which increased their susceptibility to P. notatus predation

• At low flash frequencies, strike success was greater at illuminated mysids than at nonilluminated mysids • As flash frequency increased, strike success decreased at both illuminated and nonilluminated mysids, but illuminated targets were always more vulnerable

• The time between flash onset and strike initiation also effected strike success • High strike success was observed when predatory strikes were launched within 1000 msec of flash onset • Delays over 3000 msec reduced success rates by almost 50%

PHYLOGENY

FUTURE PROBLEMS • While the genes for many luciferases are known, the mechanisms of luciferin biosynthesis are almost entirely unknown. • Better access to live animals in good condition will give opportunities to understand natural functions of luminescence. • the chemistry of luminescence for many organisms remains completely unknown

FUTURE RESEARCH • Glowing trees to line highways to save governement electrical bills • Christmas trees • Crops and domestic plants that luminesce when they need watering • Bio-identifiers for escaped convicts and mental patients

SOURCES • Mensinger, Allen F. "Ecomorphological Adaptations to Bioluminescence in Porichthys Notatus. " Environmental Biology of Fishes 44 (1995): 133 -42. • Haddock, H. D. "Bioluminescence in the Sea. " Annual Review of Marine Science: 443 -93. Web. 2010.