bioluminescence

"hey, baby"

a portrait of the artist as a ctenophore

i have been fascinated by bioluminescence since long before i knew it by that name. one of the best things about growing up in the northeastern united states on a farm with big grassy meadows was the abundance of fireflies- a nightly summer sight that will always top my list of things i miss most  about the east coast. as an undergraduate, i learned that unlike the handful of terrestrial species (such as fireflies) that glow at night, the marine environment is home to thousands of species that produce their own light. mind blowing! more important than the facts i learned, however, were the many experiences i was fortunate to have involving some of those creatures. again, i managed to matriculate in an area (long island’s east end) where fairly often, there was low enough ambient light and high enough concentrations of bioluminescent critters in the sand that night time walks on the beach (taken with great frequency by procrastinating college students) were often a dance workout, wherein groups of us would drag our feet and hands along the wet sand on the edge of the ocean in order to watch the streaks of glowing light.

as a SEAmester student, i was  immersed in bioluminescent experiences figuratively (almost nightly our schooner created a glowing bow wake, just from sailing through the water and disturbing the dinoflagellates swimming there, causing them to emit their glow) and literally (we took a swim in a bioluminescent bay in la parguerra, puerto rico, and got to watch our own bodies glowing head to toe from the plankton adhered like dot-to-dots along our skin and swimsuits). one of my favorite visions of all time is watching dolphins race along beside the boat, the night too dark to actually see them, but knowing their presence from the way the water was streaked with light and the sound of their exhalations each time they’d surface. i continued my love affair with bioluminescence later on when i was employed as a professional mariner (doesn’t that sound more awesome than “deckhand” or “schooner bum”?) and have been known to jump in the water at night, right off the side of the ship in port, even in places (filled with ctenophores) as unlikely as new jersey.

glowing ctenophore in watercolor, tweaked in photoshop

shine your light

“the question of why so many animals are bioluminescent still does not have a satisfactory answer.” – S. Haddock (et al.) bioluminescence in the sea (annu. rev. mar. sci. 2010 2:443-93.) (gotta love the open access movement in the scientific literature… you, too, can read this review- all 50 pages! i know you’re as excited as i was!)

translation: “we dunno.” -me

what do the leading scientists in the field mean, they don’t know?! let’s break it down. we are talking about generating light on a cellular level. light, radiating not from the sun, not from electrical current…. but from reactions that take place within the very cells of the organism. light from within living beings. and get this, according to wikipedia, “all cells produce some form of bioluminescence within the electromagnetic spectrum, but most are neither visible nor noticeable to the naked eye. every organism’s bioluminescence is unique in wavelength, duration, timing and regularity of flashes.” all cells! that includes mine, and yours, and everyone else’s! we all have the ability to generate light from within, and illuminate the darkness surrounding us. now if that’s not a sacred truth brought straight to you by the natural world, i don’t know what is.

so it turns out, science can unlock all sorts of mysteries of how the chemistry and physics and biology behind this phenomenon work, what enzymes catalyze which reactions, and so on. but science isn’t satisfied with the explanations of why these things even happen (though science assumes it will someday know…)  for me, the question itself  is where i find  satisfaction, i am just as happy as a bioluminescent bivalve that these mysteries exist and even happier that yes, it is possible that some questions will never be answered by science. i think it is important, as scientists, as human beings, to hold that space for the possibility of mystery.

but before i get carried away with the spiritual aspects of bioluminescence,

a few definitions

bioluminescence, simply put, is the emission of light by living organisms, and it also refers to “the light so produced”. either way, what we have here is a noun. creatures are said to be bioluminescent (adj.) if they are capable of pulling off this amazing feat. as mentioned, we are all bioluminescent- it’s just that the particular wavelength we emit may not always fall within the visible-to-us portion of the spectrum.

not to be confused with some related phenomena:

fluorescence: light produced when external energy is absorbed by the organism, and then emitted again by it immediately.

phosphorescence: a form of fluorescence where the energy is absorbed, stored and slowly re-emitted (in this case, we’re still getting energy from an external source. think glow-in-the-dark star stickers on your ceiling- they need to be charged up by having light shined on them.) the term phosphorescence was in vogue for a long time, and often used interchangeably to refer to what we now understand to be bioluminescence.

“PHOSPHORESCENCE. Now there’s a word to lift your hat to…to find that phosphorescence, that light within, that’s the genius behind poetry.” ~ Emily Dickinson

noctiluca scintillans, a bioluminescent dinoflagellate (roughly 1 mm in size)

bioluminescence, on the other hand, is light actually produced from within the organism. no external energy source! ok, technically we’re all solar powered either directly through photosynthesis, or indirectly through eating photosynthetic beings, but the light in this case is not just re-emitted sunlight, it is generated by a chemical reaction within the cells of the organism.

light, in general, is produced when an electron absorbs energy, is excited (moved) to a higher orbit, and releases a photon (packet of energy) as it falls back to its home orbit. in bioluminescence, that excitation happens due to a chemical reaction. luciferins are the chemicals involved in making light. luciferases are enzymes that catalyze the oxidation reactions that produce the light (via the oxidation of the luciferins).

in many cases, the organism does not produce its own luciferins, but obtains them through “trophic interactions,” in other words, they have to eat the right thing to be able to shine. (can you relate?) because, get this: some luciferins are related to chlorophyll- some of them only require the rearrangement of a few metal ions in order to switch from chlorophyll to luciferin. scientists speculate that the organisms at the bottom of the food web who are capable of making this compound may actually convert back and forth between the two on a diel basis (opting for chlorophyll during daylight hours when the absorption of sunlight is key, and switching to luciferin after dark when it’s time to emit light instead). wow, neat!

shine on you crazy diamond

now i am going to attempt to think across disciplines and touch on the spiritual significance of these crazy light makers. filling our heads with a bunch of data is all well and good, but what about tapping into some of that dinoflagellate and firefly medicine? what can we learn about our own souls by dwelling on the attributes of ctenophores and cephalopods? spirit guides (or in quinn’s recent terminology “spirit guys” as he announced of the dinosaurs he was drawing the other night) are our animal and plant brothers and sisters, to whom we can look for information about how we process the world around us. there is a lot of wisdom in nature, waiting there for us to just open our eyes and receive it. traditionally, a lot of literature on spirit helpers (also known as totem animals) focus mainly on vertebrates (birds, mammals, perhaps a reptile or two, occasionally a fish) and rarely you can even read about spirit guidance from the plant people, and even more rarely, from invertebrate animals, such as spiders or dragonflies, for instance. as we all know, however, most of nature is not made up of vertebrates, so i believe it is important to look far beyond the charismatic megafauna for the truths nature holds for us. i will be the first to admit that i go for the charismatic megafauna types, don’t get me wrong: dolphins are my numero uno totem, but i like to look to the sea urchins and the kelp for their wisdom too. the bioluminescent beings seem to have their own special brand of wisdom to gift us with. small though they might be, they are responsible for most of the light produced in the majority of the ocean’s volume! i am only going to go into detail on a small handful of light producing critters and their medicine, just to give you an idea of some of the endless possible ways you can use the spiritual truths found in nature to enhance your own spiritual walk.

dinoflagellates

these are single celled marine algae that make up a huge part of the base of the food web in the ocean. some are photosynthetic (over half), some heterotrophic (that means they engulf/eat other organisms), some are endosymbiotic zooxanthellae (meaning they live inside other creatures, for example corals, in a symbiotic mutualistic relationship) and still others parasitic. shall we say, they’re adaptable? always a nice trait to embody. so wait a minute, are they plants or are they….? yep, as heterotrophic photosynthetizers, dinoflagellates blur the lines between plant and animal, which makes me love them all the more. i think it’s important to realize that classification (taxonomy) is always a best guess/approximation and that nothing is ever truly black and white. i love organisms that defy our dualistic paradigms.

pyrocystis fusiformis dinoflagellate (~1mm)

dinoflagellates bioluminesce only upon disturbance. now there’s a spiritual tool for you- to learn how to glow your brightest when life sends you disturbances. they are responsible in large part for the glowing bow wakes, dolphin trails, and sparkling beach sand: if you drive your boat into them, they glow. again, we do not know exactly why they glow, but some speculate that they glow when a predator arrives to munch them, perhaps as a distraction; others think they do it to attract yet larger predators to the scene to take care of their predators. all i know is there is a lot to be learned from these 1-mm small beings. small is mighty! indeed, dinoflagellates are the organisms responsible for harmful algal blooms known as red tides- they are powerful indeed and not to be trifled with!

ctenophores:

off the top of my head, some of the attributes of comb jellies or ctenophores, who belong to their very own phylum (ctenophora) are: symmetry, simplicity, efficiency, flow, buoyancy, transparency… yet for all their grace and slow, quiet, twinkliness, they are voracious carnivores, again capable of achieving devastating results when too many of them bloom in one place. they waste no energy, producing nothing but light (no heat) from their glow, which in the case of ctenophores is again, maybe a defensive response, kind of a fake-out smoke-screen strategy.

they’ve got rhythm- their cilia (the “combs” of comb jellies) beat in a coordinated, sequential way- think of doing “the wave” at a baseball stadium. something else they can do is incorporate the stinging nematocysts of the prey they consume into their own tentacles- another one of those handy skills to be packing.

fireflies:

fireflies are a type of beetle (not flies, after all) making up the family lampyridae. all the eggs and larvae, and many of the adults of the various firefly species can luminesce. the larvae (who eat slugs- now there’s a trait i like in a totem animal, preying upon my gardening nemesis!) are presumed to be broadcasting that “we don’t taste good” through their use of bioluminescence, while the adults (who light up their abdomens in flash dialogues) are thought to primarily use light in mate attraction. they are tricky, though, and in some cases fireflies have been observed to lure in members of other firefly species by mimicking that species’ flash type, then gobbling them up when they unsuspectingly land hoping to mate. fireflies may also use light as a defensive mechanism- making light is useful, and not at all reserved for just one strategy.

again, the reaction going on in fireflies to create the light gives off almost no heat; compare this nearly 100% efficiency to that of an electric light bulb, which loses 90% to heat and turns only 10% of the energy into light. how do they turn their love light on (and off?) well, the  “exact mechanism has yet to be worked out.” translation: “we dunno.” (sounding familiar?)

the author begs your forgiveness for the scientific inaccuracy of these quick sketches- not intended for any kind of official use, just eye candy for my post!

dragonfish

i could not leave out dragonfish; though i did very little reading on them, other than in quinn’s copy of one nighttime sea, i couldn’t help but see the parallel between these dragons of the sea, and my dragons of the air, about which i posted a similar science-geek-spirit-helper-fest a few months back.  these crazy deep-sea fish can produce light in both the blue-green portion of the spectrum, and the red. this red light is especially unique in the deep ocean, where it cannot be seen without special tricky adaptations, and points to a truth about light and vision- that not only does the organism have to have the equipment to produce the light, it also must be able to see it. in the deep sea, almost nobody retains the ability to see red, but these dragonfish are true visionaries, and they can use this special red light to all kinds of advantage in the darkest of dark environments. more little dragons doing awesome things.

choose your own glowing totem

many, many other species display bioluminescence- this is only a very tiny sampling. in fact, according to the review i quoted above, it is estimated that bioluminescence evolved over 40 times, independently, just in the marine environment. but if it’s so darn useful, why doesn’t every marine (or freshwater, or terrestrial) organism produce visible light? you guessed it- we dunno. there are hardly any cases of bioluminescence observed in freshwater- such a striking contrast with the glowing ocean. i highly recommend reading up on more of these fascinating organisms, and incorporating them as your very own glowy spirit helpers.

light up your life

“we rode back to the ship on a carpet of stars and comets and streaks of lightning- some of the most amazing bioluminescence i’ve ever seen. i  leaned over the rail of the boat, watching the moon and the glowing feeding frenzy alternately” ~me, 3-17-01, mexico

want to go dancing on the stars, and swimming in sparkly water? it’s something i plan my vacation time around, and you can, too. a little internet searching can let you know what your best bet is for landing in a field of fireflies, or showing up on a beach at the most auspicious time for sparkling sand encounters. here on the oregon coast, i haven’t had any opportunities (yet!) to encounter bioluminescence, but now that quinn is a bit older, i plan to make it a priority for this summer to go walk on the beach under new moon darkness. summer is when nutrients and sunlight are more readily available to nourish plankton and also when we will be least likely to freeze our heinies off on the beach at night! happy coincidence. we hope to make an east coast pilgrimage in the warmer months, for a firefly encounter (oh yeah and to see family- just kidding, family is actually the priority but the fireflies will be a bonus!) i am also slated to be on a research cruise at the end of june, and am hopeful to see some bioluminescence while i’m out to sea.

here are some resources, if you want to do more reading:

the bioluminescence web page (full of illuminating info! including ways you can grow bioluminescent plankton at home– care to light up your homeschooling/unschooling science scene anyone?)

got older kids who want to see the (glowing) world? semesters at sea for high school and college students

here’s where i got some of my firefly info.

while you’re learning about bioluminescence, another aspect that is great to cover is conservation. like any other insect, fireflies are sensitive to the pesticides used so heavily in our current agricultural scheme. ocean health and plankton health are certainly sensitive to many anthropogenic disturbances as well. there are many rabbit holes to go down on this topic, but i’m refraining from mentioning too many depressing ones in this post- this one, i just wanted to let shine. 😉

other posts you may enjoy:

6 comments to bioluminescence

Leave a Reply

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>