2004 Deep-Scope Expedition Who Has the ?

FOCUS TEACHING TIME in deep-sea organisms One 45-minute class period, plus time for student research GRADE LEVEL 7-8 (Life Science) SEATING ARRANGEMENT Classroom style or groups of 3-4 students FOCUS QUESTION What deep-sea organisms are capable of bio- MAXIMUM NUMBER OF STUDENTS luminescence, and how does this ability benefit 30 these organisms? KEY WORDS LEARNING OBJECTIVES Students will be able to compare and contrast Bioluminescence chemiluminescence, bioluminescence, fluores- Fluorescence cence, and phosphorescence. Phosphorescence Luciferin Students will be able to explain at least three ways in which the ability to produce light may be useful to deep-sea organisms. Counter-illumination

Students will be able to explain how scientists BACKGROUND INFORMATION may be able to use light-producing processes in Deep-sea explorers face many challenges: deep-sea organisms to obtain new observations extreme heat and cold, high pressures, and of these organisms. almost total darkness. The absence of light poses particular challenges to scientists who want to MATERIALS study organisms that inhabit the deep ocean envi- ❑ None ronment. Even though deep-diving submersibles carry bright , simply turning these lights on AUDIO/VISUAL MATERIALS creates another set of problems: At least some ❑ (Optional) Images of deep-sea environments mobile organisms are likely to move away from and organisms that use bioluminescence (see the light; organisms with light-sensitive organs Learning Procedure) may be permanently blinded by intense illumina- tion; even sedentary organisms may shrink back, ceasing normal life activities and possibly becom- ing less noticeable; and small cryptic organisms 1 2004 Deep-Scope Expedition – Grades 7-8 (Life Science) Focus: Bioluminescence in deep-sea organisms oceanexplorer.noaa.gov

may simply be unnoticed. In addition, some orbitals, energy is released in the form of important aspects of deep-sea biology simply visible light. can’t be studied with ordinary visible light. Many marine species are known to be capable of pro- Chemiluminescence is distinctly different from ducing light, and it is reasonable to suppose that fluorescence and phosphorescence, which occur ability to produce and detect light might be par- when electrons in a molecule are driven to a ticularly important to organisms that live in near- higher-energy orbital by the absorption of light total darkness. energy (instead of chemical energy). Both pro- cesses may occur in living organisms. Atoms The primary purpose of the 2004 Ocean of a fluorescent material typically re-emit the Exploration Deep-Scope Expedition is to study absorbed radiation only as long as the atoms deep-sea biological communities using advanced are being irradiated (as in a fluorescent lamp). optical techniques that provide new ways of Phosphorescent materials, on the other hand, looking at organisms that make their home in the continue to emit light for a much longer time after blackness of the deep ocean. These techniques the incident radiation is removed (glowing hands are based on a number of basic concepts that on watches and clocks are familiar examples). can be summarized under the general heading of Chemiluminescent reactions, on the other hand, “bioluminescence.” produce light without any prior absorption of radiant energy. Another light-producing process Bioluminescence is a form of chemiluminescence, known as triboluminescence occurs in certain which is the production of visible light by a crystals when mechanical stress applied to the chemical reaction. When this kind of reaction crystal provides energy that raises electrons to a occurs in living organisms, the process is called higher-energy orbital. bioluminescence. It is familiar to most of us as the process that causes to glow. Some of us The production of light in bioluminescent organ- may also have seen “foxfire,” which is caused isms results from the conversion of chemical ener- by bioluminescence in fungi growing on wood. gy to light energy. The energy for bioluminescent Bioluminescence is relatively rare in terrestrial reactions is typically provided by an exothermic ecosystems, but is much more common in the chemical reaction. marine environment. Marine organisms producing bioluminescence include bacteria, algae, coelen- Bioluminescence typically requires at least three terates, annelids, crustaceans, and fishes. components: a light-emitting organic molecule known as a luciferin; a source of (may

The fundamental chemiluminescent reaction be O2, but could also be peroxide or a occurs when an electron in a chemical molecule similar compound); and a protein catalyst known receives sufficient energy from an external source as a luciferase. In some organisms, these three to drive the electron into a higher-energy orbital. components are bound together in a complex This is typically an unstable condition, and when called a photoprotein. Light production may be the electron returns to the original lower-energy triggered by the presence of ions (often calcium) state, energy is emitted from the molecule as a or other chemicals. Some bioluminescent systems photon. Lightning is an example of gas-phase also contain a fluorescent protein that absorbs the chemiluminescence: an electrical discharge in light energy produced by the photoprotein, and re- the atmosphere drives electrons in gas molecules emits this energy as light at a longer wavelength.

(such as N2 and O2) to higher-energy orbitals. Several different luciferins have been found in When the electrons return to their original lower- marine organisms, suggesting that bioluminescence

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may have evolved many times in the sea among should understand that every light-producing different taxonomic groups. Despite these differ- process requires a source of energy (chemical, ences, almost all marine bioluminescence is green electrical, mechanical, or light). Tell students to blue in color. These colors travel farther through that bioluminescence is a form of chemilumi- seawater than warmer colors. In fact, most marine nescence that occurs in living organisms, but organisms are sensitive only to blue light. do not explain the details of bioluminescence at this point. Students may ask about incandes- In this activity, students will research biolumi- cence, in which light produced by combustion nescence in a variety of marine organisms, and reactions (thermal energy). Review the concept draw inferences on how the ability to produce of the visible and near-visible light spectrum. light may benefit the organisms and how scientists Students should understand that light at the blue may use light-producing properties for research. end of the spectrum (including ultraviolet light) has higher energy than light at the red end of LEARNING PROCEDURE the spectrum (including infrared). 1. If you want to include demonstrations of chemi- luminescence, bioluminescence, fluorescence, 3. Tell students that their assignment is to investi- and phosphorescence, see the ‘Cool Lights” gate light-producing processes in one or more lesson plan for suggestions. The following web marine organisms, and prepare a report that sites are useful resources if you want to show contains answers to the following questions: images of deep-sea environments and organ- • What is the basic chemistry of biolumines- isms that use bioluminescence: cence? http://www.biolum.org/ • What color is bioluminescence? http://oceanexplorer.noaa.gov/gallery/livingocean/livingocean_coral. • How does your organism use biolumines- html cence? http://www.europa.com/edge.of.CyberSpace/deep.html • Some animals that are capable of biolumines- http://www.europa.com/edge.of.CyberSpace/deep2.html cence seem to have no use for the light they http://www.pbs.org/wgbh/nova.abyss/life.bestiary.html produce. What are some explanations for http://biodidac.bio.uottawa.ca/ this? http://www.fishbase.org/search.cfm • How does the light output from biolumines- cence compare to a 100-watt light bulb? 2. Ask students to describe characteristics of deep- • What are some practical uses of biolumines- sea environments (depth = 1,000 meters or cence? more). You may want to show images of vari- ous deep-sea environments and organisms that As part of their research, challenge students to use bioluminescence. solve the mystery of the color-changing (from http://www.lifesci.ucsb.edu/~biolum/organism/squid.html). Focus the discussion on light in the deep ocean. Many have their lower (ventral) surfaces Students should realize that light is almost covered with small light-emitting photophores completely absent. Ask whether plants and ani- which put out a soft glow when the squid turns mals are ever able to produce their own light. them on. These squids also move vertically Most students will be familiar with fireflies, through the water each day (vertical migration). and may mention bioluminescence in other They stay down deep during the daylight, but species. Review the basic concept of chemi- come up to the surface at night under cover of luminescence, and contrast this process with darkness. How are photophores on the ventral fluorescence and phosphorescence. Students surfaces useful to the squid?

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Assign one or more of the following organisms to • What color is bioluminescence? each student or student group: Bioluminescence comes in all colors, red, Bacteria orange, yellow, green, blue and violet, but most marine bioluminescence is blue or blue- green. Light at the blue end of the spectrum Ctenophores (comb jellies) has higher energy than light at the red end Mollusca of the spectrum. Consequently, blue light Squid penetrates farther through seawater than Annelid worms light having longer wavelengths (toward Polychaetes the red end of the spectrum). Most marine Crustaceans organisms only seem to be able to detect Ostracods blue light. Amphipods Decapod shrimp • How may deep-sea organisms use Euphausiids () bioluminescence? Echinoderms Some organisms seem to use biolumines- Urochordates cence to locate other members of the same Chordates species, and we infer that this would be Sharks useful for mating activities. Bioluminescence Fish may also be useful for feeding. Some organ- Anglerfish isms (such as the angler fish) use biolumines- Black Dragonfish cence to attract prey species. Others (such Malacosteids as fishes in the malacosteid family) have a “floodlight” system that allows them to see 4. Have each student or student group present and nearby organisms. These fishes have organs discuss the results of their research. Points that that produce red light (an exception to the should emerge during these discussions include: “blue only” rule), as well as eyes that can • What is the basic chemistry of biolu- detect red light. Since most other species minescence? (so far as we know) cannot see red light, Bioluminescence typically requires a light- the malacosteids can sneak up on their prey emitting organic molecule known as a without being detected. luciferin, a source of oxygen, and a protein catalyst () known as a luciferase. A third potential use for bioluminescence The luciferin receives energy from a chemi- is camouflage. It may not be immediately cal reaction catalyzed by the luciferase and obvious how emitting light could make an using oxygen, then releases the energy in organism less visible, yet this is the strategy the form of light. involved in counter-illumination. You can illustrate this by holding a white index card A few animals, like the angler fish, grow against a window in a darkened room. The in their light organs. card will block out light coming through the In this mutualistic symbiotic relationship, window and be visible as a darker object the fish supplies bacteria with food and the against the bright background. If you shine bacteria provide the fish with light needed to a flashlight on the card, the illumination on attract prey. the “dark” side of the card will be closer to

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that of the background, making the card less per second, while a single bioluminescent visible. Counter-illumination could thus be a will emit 1010 to 1011 photons useful strategy to a swimming organism try- per second. A 100-watt light bulb emits about ing to be less visible to a potential predator 1018 photons per second. So you would swimming below. need 107 to 108 (ten to one hundred million) dinoflagellates all flashing at once to equal Some animals use bioluminescence for the light output of a single 100-watt bulb. Of defense in a different way. Some tube-dwell- course, the light bulb stays lit continuously, ing worms spew out clouds of glowing blue while the output of the dinoflagellates is inter- material when they are threatened. The mittent. strategy is similar to the fear scream of mon- keys or birds, which are intended to attract • What are some practical uses of bio- the attention of higher order predators that luminescence? may attack the threatening predator. So Answers may include: the glowing cloud produced by the worm – Bacterial bioluminescence is used to test exposes the threatening invader and makes for contaminants in food. the invader vulnerable to attack by a higher – Chemicals from jellyfish are used in genet- order predator. ic research to allow researchers to see when a gene is activated. It is important for students to realize that – Fluorescent proteins from jellyfish are also since explorations of deep-sea communities used to design living systems for the explora- are just beginning, we almost certainly don’t tion of other planets (see the “Lights in the know all of the ways that these processes Deep” lesson plan for more details). are used by deep-sea organisms. 5. Discuss how light-producing processes and the • Some animals that are capable of ways they are used by deep-sea organisms bioluminescence seem to have no use could be useful to scientists exploring deep for the light they produce. What are ocean environments. The 2004 Deep-Scope some explanations for this? Expedition will use several techniques to make One possibility is that bioluminescence in observations that have never been made these animals is a vestigial adaptation that before. A new deep-sea observatory called was useful at some point in the animal’s evo- Eye-in-the-Sea can be placed on the bottom and lutionary history, but is no longer useful. But left alone to observe sea life without interfer- since bioluminescence requires considerable ence from a submersible vessel. The observa- energy, it is unlikely that such an adaptation tory is capable of capturing video images would persist if it had no survival value. A using only red light (which should be invisible more likely explanation is that we simply to many organisms) and can be programmed don’t know enough (yet) to understand why to acquire time-lapse images (one minute of bioluminescence is useful to these animals. recording every fifteen minutes) over several days. The video recording system can also be • How does the light output from bio- programmed to respond to bioluminescence, so luminescence compare to a 100-watt that whenever a bioluminescent event is detect- light bulb? ed, the recorders will start to capture additional One bioluminescent bacterium produces bioluminescent images, then will turn on the red about 1000 to 10,000 (103 to 104) photons illumination to capture an image of organism

5 2004 Deep-Scope Expedition – Grades 7-8 (Life Science) Focus: Bioluminescence in deep-sea organisms oceanexplorer.noaa.gov

producing the bioluminescence. html for sources and demonstration ideas. Fotodyne, Inc. offers kits for demonstrating Other observations will use ultraviolet light bacterial bioluminescence (see http://www.foto- to search for fluorescent organisms that may dyne.com/education/safelumi.php) be less visible under “white” light. A related study will measure the spectral reflectance of RESOURCES captured organisms, to determine what kinds http://www.lifesci.ucsb.edu/~biolum/ —The Bioluminescence of illumination will make these organisms most Web page visible to observers. Yet another series of stud- ies will investigate whether polarized light is http://www.nightsea.com/ – Web site offering products for used by deep-sea organisms, how polarized studying fluorescence underwater light is changed by these organisms and deep- sea water, and whether these changes can be http://www.flinnsci.com – Web site for Flinn Scientific, detected and recorded. Inc., source for materials for demonstrating chemiluminescence; Phone 1-800-452-1261 THE BRIDGE CONNECTION www.vims.edu/BRIDGE/ – Click on “Biology” in the http://www.biolum.org/ – Harbor Branch Oceanographic navigation menu to the left, then “Plankton,” then Institution Web site on bioluminescence “Phytoplankton” for resources on ocean food webs. Click on “Ecology” then “Deep Sea” for http://ice.chem.wisc.edu/materials/light/lightandcolor7.html – Web resources on deep sea communities. site with links to other activities involving fluorescence and phosphorescence THE “ME” CONNECTION Have students write a short essay about how bio- http://oceanexplorer.noaa.gov/gallery/livingocean/livingocean_coral.html luminescence affects (or might affect) their own – Ocean Explorer photograph gallery lives. http://oceanica.cofc.edu/activities.htm – Project Oceanica Web CONNECTIONS TO OTHER SUBJECTS site, with a variety of resources on ocean English/Language Arts, Earth Science, Physical exploration topics Science NATIONAL SCIENCE EDUCATION STANDARDS EVALUATION Content Standard A: Science As Inquiry Written reports provide opportunities for assessment. • Abilities necessary to do scientific inquiry • Understandings about scientific inquiry EXTENSIONS 1. Have students visit http://oceanexplorer.noaa.gov to Content Standard B: Physical Science find out more about the 2004 Deep-Scope • Properties and changes of properties in matter Expedition and about opportunities for real- • Transfer of energy time interaction with scientists on current Ocean Exploration expeditions. Content Standard C: Life Science • Structure and function in living systems 2. Bioluminescence can be demonstrated with • Diversity and adaptations of organisms several organisms. Dinoflagellates are wide- ly used; see http://siobiolum.ucsd.edu/Biolum_demos.html and http://www.lifesci.ucsb.edu/~biolum/organism/dinohome.

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Content Standard F: Science in Personal and Social Perspectives • Populations, resources, and environments • Science and technology in society

FOR MORE INFORMATION Paula Keener-Chavis, National Education Coordinator/Marine Biologist NOAA Office of Exploration Hollings Marine Laboratory 331 Fort Johnson Road, Charleston SC 29412 843.762-8818 843.762-8737 (fax) [email protected]

ACKNOWLEDGEMENTS This lesson plan was produced by Mel Goodwin, PhD, The Harmony Project, Charleston, SC for the National Oceanic and Atmospheric Administration. If reproducing this lesson, please cite NOAA as the source, and provide the follow- ing URL: http://oceanexplorer.noaa.gov

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