The Cartesian Diver: this is a classic demo named after the17^th-century philosopher and mathematician René Descartes.

Buoyancy is the force that decides whether an object will sink or float, and has had a long and colorful history. As the story goes, the Greek thinker Archimedes was sitting in his bathtub one day when he noticed how the water around him rose when he got in. Suddenly, he realized that he could use the water level rise to measure an object’s volume. Shouting “Eureka!” he burst out of the tub and ran out into the streets stark naked.

Fascination with buoyancy continues into modern times. Astronauts have exploited buoyancy to simulate being in space. Scuba divers use it to turn the underwater world into their playground. And then of course there is David Letterman’s Will it Float?, an entire sketch dedicated to watching what happens when something is dropped into a giant pool of water. Demonstrations at home of buoyancy are easy to come by, too. Below are two of my favorites.

Cartesian Diver

This is a classic demo named after the17^th-century philosopher and mathematician René Descartes, although curiously, no one seems to know why. Build a miniature model of a submarine here and take control of an object’s depth.

What to do: You need a 2-liter plastic soda bottle, the cap to a ballpoint pen, water, and a lump of clay. Drain the soda bottle and refill with water. Attach a lump of clay to the bottom of the pen cap (enough to weigh it down but not quite to sink it). Drop the cap into the filled soda bottle and seal the bottle’s top. Squeeze! Depending on the amount of pressure you apply, you should be able to make your pen cap dive to the bottom of the bottle and resurface at will.

What’s going on? An object will float or sink depending on how its density (its mass divided by its volume) compares with that of the surrounding liquid. For example, a steel rod is heavy for its size so it sinks. However, if you increase the rod’s volume by trapping an air bubble inside or reshaping the steel into a boat, then you can make it float. In the case of the Cartesian diver there is an air bubble trapped beneath the pen cap. When you squeeze the bottle you compress the air bubble into a smaller volume, and while the diver still weighs the same it now sinks. This is exactly how the ballast tanks of a submarine work, and many fish have an organ called a swim bladder that uses the principle to control their depth.

Layered Liquids

Awesomeness ensues when you mix the effects of buoyancy with liquids that don’t mix. You may already be familiar with the fancier versions of this demo in the form of lava lamps or the oil drop toys you can buy in many trinket stores.

What to do: You need corn syrup, water, vegetable oil, a clear container, and some food coloring. Use the food coloring to dye the corn syrup, water, and oil different colors for increased effect. Pour about an inch of corn syrup into the bottom of the clear container, then gently pour about an inch of water above it, and finally pour the oil atop the water. Each liquid will float atop the one beneath it.

What’s going on? Density can affect whether or not a liquid will float in exactly the same way that it can determine whether a solid object floats. In this example water is less dense than corn syrup, so it floats on top. Oil is less dense than both corn syrup and water, so it floats highest of all. Such layering of liquids can also happen between salt water and fresh water in underwater caves, sometimes dangerously tricking divers into believing there is an air bubble over their heads when in fact there is just a different kind of water.

It was the poorly constructed, mostly concrete buildings that killed most of the victims of the earthquake in Haiti.

Like a lot of people, I’ve been thinking about the devastation from the earthquake in Haiti, seeing images of collapsed buildings and dead people on the news and in the newspapers. I wonder why less than a hundred people in the Bay Area died in the Loma Prieta earthquake in 1989, and perhaps as many as 200,000 have died from the earthquake last month in Haiti. The Transamerica Building in downtown San Francisco swayed about one foot at the top during the Loma Prieta earthquake, but the building was not damaged. We’ve all seen pictures of what happened to Haiti’s Presidential Palace in Port au Prince.

I did an Internet search and discovered the Pacific Earthquake Engineering Research Center (PEER) at Cal Berkeley. PEER is an interdisciplinary organization that studies the effect of earthquakes on structures and how to build safe structures in earthquake zones. PEER asked a structural engineer, Eduardo Fierro, P.E., of Bfp Engineers in Berkeley, to travel to Haiti and make a preliminary report on the damage there. This is Fierro’s two-hour presentation at Cal Berkeley from the PEER Web site. Fierro knows his stuff when it comes to structures, but in the video he shows that, for him, it is a matter of the heart as well as the head.

I am not a structural engineer, but I remember enough from my mechanical engineering courses to understand the basics of building in an earthquake zone, and the PEER video was like a two-hour refresher course.

I know that in order for a concrete building to handle its own weight (compression), as well as lateral forces (tension), the concrete must be reinforced with steel bars. The steel can handle the tension while the concrete can handle the compression.

I do know that it was the poorly constructed, mostly concrete buildings that killed most of the victims of the earthquake in Haiti. Buildings slid off their foundations if they were not bolted to the foundation, floors collapsed because of shear stress and the lack of sheer walls, and poorly reinforced concrete pillars holding up buildings collapsed.

There are no enforced building codes in Haiti. The concrete quality used in buildings in Haiti is poor, and the installation of concrete is done poorly. The concrete is brittle, and the steel bars used to reinforce it are too thin; there are not enough of them; and when a concrete pier comes together with the concrete floor of a second story, for example, the vertical reinforcing bars in the pillars are often not connected to the horizontal bars in the floor, meaning that the building has no integrity.

A few buildings near the epicenter of the earthquake held up well, but this is not because of the quality of the construction. The intact buildings are built on solid rock, so that the rock absorbed the shock of the quake, so the building didn’t have to. Within loose soil, an earthquake causes a phenomenon called liquefaction. The soil becomes like liquid, and passes most of the force of the earthquake into the building above the soil.

Perhaps the saddest thing that Fierro reported was the fact that, already, people are picking up the pieces of broken buildings, and building structures in the same old way. It’s a poor country with a history of conflict and oppression. It may be the best the Haitian people can do, without the help of wealthier nations.

By using water as a commodity, we are using up the fresh water the planet provides faster than it can replenish it.

Reporting this piece introduced me to a subculture I hadn't paid much attention to before: Water nerds.

It turns out I sit right next to a couple of them, right here at KQED. One is named Dan Brekke. He's an editor here. Dan spouts off reservoir levels the way other people recite batting averages.

Monthly snowpack surveys are awaited with baited breath. Curious about the state's current hydrological conditions? Dan can probably tell you.

Speaking of snowpack surveys, don't miss Craig Miller's Climate Watch video about how the surveys are conducted and what they mean. (See, I told you this place was crawling with water nerds.)

Anyway, it seemed unfair that I, an amateur water nerd, should be allowed to actually meet weather celebrities like Jan Null, a meteorologist for the Golden Gate Weather Service (and a favorite source of KQED reporters). My trip out to Folsom Dam made me the envy of the newsroom. But Dan didn't hold it against me. In fact, he agreed to share his interactive map with me, which he has promised to update daily with reservoir levels. (For a larger view, click here.)

He must be looking for converts.

View KQED: California Reservoir Watch in a larger map

Listen to Is The Drought Over? radio report online.

A giant ground sloth (Eremotherium eomigrans) from the upcoming exhibit, "Extreme Mammals" at the California Academy of Sciences. © AMNH/D. Finnin

Time is measured a bit differently by those who work in a museum. Exhibits both permanent and temporary have a lot to do with this. When I first started working at the California Academy of Sciences, my whole schedule was dictated by "Chocolate: The Exhibit". When an exhibit is close to completion, there is a palatable energy felt by those who have worked on it. This is not a small number of people; most museum employees have some small part of making exhibits ready for the public – from installing, text work, cleaning specimens to graphics, marketing, and educating the public on the content. Time, for a museum employee, doesn’t so much change with the seasons but with new installments.

With that said, I was eager today to walk around the newly renovated, "Altered State: Climate Change in California" exhibit. The 80-foot-long blue whale skeleton still shadows the footprint of the space. However, there are some old favorites back on display such as the sequoia redwood round that is over 1700 years old. (The last time it was on display was for the Hotspot exhibit at our temporary facility on Howard Street). The exhibit also has a presentation area to learn about what guests can do to be more sustainable and a rotating globe front and center.

Space was also made in the exhibit to introduce an upcoming exhibit, "Extreme Mammals", which will run from April 3-September 12, 2010 on the second floor of the museum. There is a bare stage on the peripheral of Altered States. It has been set-aside for a specimen that will be extreme in size.

So what will "Extreme Mammals" be about? The exhibit will display the biggest, smallest and most amazing animals in the mammal family. It will have a montage of fossils, reconstructions, recent specimens and living animals. The exhibit will delve into surprising and extraordinary traits in extinct and living animals. Some questions that might be answered include:

Could a whale walk?

Could a bat be the size of a bumblebee?

Could a mother be pregnant for almost two years?

Staff has been counting down to April 3rd and the opening of "Extreme Mammals" – literally! There is a huge countdown calendar upon entry to the staff offices and everyone who works here sees it on a daily basis. We are currently on day 60. The countdown started on day 75 and will be complete on April 3rd. Like I said, new exhibits and installments measure time, for a museum employee.

Carl Sagan’s scientific career took a bruising because of his outreach work.

I am convinced that a lot of people’s misconceptions about science could be cleared up with a little outreach from scientists. I’m talking about outreach activities like creating websites that give good, reliable, understandable information, talking to school and adult groups, getting involved in museums, PBS, the Discovery Channel, etc.

Getting scientists to do any of this is the tricky part. They have no immediate incentives to do it and in fact, there are disincentives. But they need to learn that it is in their best interests.

Taxpayers pay most scientists’ salaries through federal grants. An uninformed, suspicious, or actively hostile public obviously will not want to pay for scientific research. So anything that can be done to inform the public about the good work being done will probably loosen the purse strings in Washington at least a bit.

Of course the problem with this argument is that it uses an abstract fear of something in the distant future. Sort of like global warming.

As we’ve learned from that, most people aren’t willing to sacrifice much for far off, future dangers. If gas is cheap, we’ll keep driving big cars. And we certainly won’t sacrifice any current goods for a future that may or may not come to pass.

Same thing with scientists. Outreach is a thankless task that can actually work against the people who do it. Scientists who do a lot of outreach are often perceived as not being serious about true science and they’re dinged for it.

There is also no incentive at Universities to do outreach. As anyone who has been involved in academic science knows, the key to success is to get government grants that help fund the scientist’s research, his or her department and the University. Everything else an academic scientist does takes a backseat to this. And outreach isn’t even in the car.

Outreach takes scientists away from the lab. It is in the lab where results are generated that can be published to get grants to fund more research. Less time on research equals less money.

So to get scientists doing outreach, we need to change the incentives. There either has to be a change at Universities so that outreach is valued. And by valued I mean tenure track positions or long term funding for people to do outreach. Frankly this is pretty unlikely.

The other possibility is to include outreach as part of a scientist’s grant. In other words, to get money for their research, scientists will need to do some outreach.

I am aware of two major funding agencies—the National Science Foundation (NSF) and the National Human Genome Research Institute (NHGRI)*—that mandate outreach for at least some of their grants. These mandates are a critical first step in getting more digestible science out to the public. But to make a major dent, we need the NIH to get involved too. They fund a whole lot more research and so a whole lot more outreach would get done too.

The NSF and NHGRI requirements are definitely causing a lot of scientists to scramble around and try to find outreach projects to fund. (Email me if you have some spare money lying around!) But I don’t know the quality of the outreach that is being done.

Hopefully the people doing outreach are better than the average scientist at talking or writing about science with the public. For the most part, the money would probably best be spent on hiring someone with a scientific background who is good at explaining science. Or in training scientists first in how to effectively communicate science to the public.

All of this points to another major issue—we need to figure out what we want from these outreach opportunities. Is it to provide a good source of information for the public? To enhance understanding of how science works? To teach people how to tell good science from bad? To train the next generation of scientists? To…? No one is really providing leadership on these questions. Let’s hope someone does soon.

*The NHGRI is interested in increasing the numbers of genomic scientists who are under-represented minorities. Definitely worthwhile but not really doing a lot for the public understanding of science.

Here is a great book on the subject: Unscientific America: How Scientific Illiteracy Threatens our Future.

Fisheries technician Wes Hartman (left) and lead biologist Ben White tag a female coho in preparation for spawning at the Warm Springs Hatchery. The tag will help match the female with males that have been selected as mates through genetic screening. Credit: Brandon Beach/U.S. Army Corps of Engineers

A short history of California salmon: Glorious past. Grim present. Dark future. Now, the story I just got done working on for QUEST Radio is about the crisis of coho salmon along our coast. But that short synopsis applies as well to coho in other parts of the state and to their larger and perhaps better-known cousins, the chinook. Wherever you look in California, salmon are in serious trouble if they have not already disappeared. It's evident that their biggest problem is having to live alongside us. Our needs and our ability to exert our will on the world around us–to dam rivers and streams, to clear forests, to replace entire ecosystems with new ones of our own making–has wrought havoc on many species.

The collapse of salmon populations is just one example. Some of the people working to preserve and restore coho along our coasts feel that history–both the natural history of the salmon and their role in human history–can be a powerful teacher and could help save the wild fish from extinction. An egg being squeezed from the vent of a female coho salmon at the Warm Springs Hatchery. Biologists at the facility examine the eggs as part of the process of determining when the females are ready to spawn. Credit: Brandon Beach/U.S. Army Corps of Engineers Biologist Rory Taylor checks on a tray of coho salmon recently hatched at the Warms Springs facility. The coho here are called "alevin"–the salmon's earliest life stage. They'll be reared in the hatchery, then planted in tributaries of the Russian River. Credit: Brandon Beach/U.S. Army Corps of Engineers

Charlotte Ambrose, the National Marine Fisheries Service biologist in charge of coordinating an upcoming recovery plan for coho along our coast, says she has this intertwined history uppermost in her mind. In fact, the draft of the 4-inch-thick recovery plan she's been working on starts with a chapter on the coho's history. Ambrose calls it "a renegade move" to open the document that way, but she says she feels it's crucial to understand the past vitality of coho on the California coast.

She's fond of quoting a 1930s account of a coho run on Northern California's Garcia River: "The water was like glass … the salmon were in rows … they lay there still … every now and then one would wiggle its tail to keep his place in line. They lay there by the thousands as far as my eye could see." That's the glorious past of the coho.

But Ambrose points out that even in that lost age, coho showed a remarkable ability to handle adversity. Drought, flood, or fire might devastate a watershed and wipe out a run. But far from being "hot-house flowers," in Ambrose's phrase, coho are survivors by nature. They're prolific breeders–a single female will lay 2,000 eggs or more in its streambed nest. If they find their natal streams unreachable, they'll wander to new spawning grounds.

Ambrose thinks an understanding of the coho's history–its ever-present drive to perpetuate itself, and its past abundance–are key elements to getting people to act to save the fish. And she says small steps to improve the odds of salmon survival can be as important as sweeping ones. "It’s like a small pebble in a pond. One small action can make a tremendous difference in increasing the probability of survival of the young, of the adults, of the eggs, of the out-migrating smolts." If we want to rewrite the next chapter of the coho's story, she suggests, get to know your watershed, and go out and volunteer to help repair it.

Listen to Saving Salmon radio report online.

Comet Wild 2, as imaged by NASA's Stardust spacecraft.

Well, at Chabot, we like to bring things down to Earth a bit—not to diminish their wonder and awe-inspiring beauty, but rather to give us a chance to connect with pieces of the Universe in a personal way that—we hope—will only enhance their wonder.

Such it is with the Personal Comet. We make them in our classrooms, and our teen volunteers—Galaxy Explorers—sometimes set up a table in our exhibits to make comets for our visitors.

Last week I was teaching a lively group of 3rd graders our class, "Shooting Stars" (I'm not the usual teacher for this class, but love teaching this one especially).

"Let's make a comet," I announced, receiving a classroomful of suddenly puzzled 8-year-old faces. "Follow me." I led the group to the back of the room and had them sit in front of our rolling comet kitchen, tying on an apron and donning the "Comet Chef" hat.

"What's in a comet?" I quizzed. Hands went up, and answers were plucked out. "Water." "Ice." "Very small pebbles."

"Good answers. Let's start cookin'…."

One by one, and two at a time, I called up volunteers (no lack of these at all) to add ingredients into the mixing bowl.

Water first—two cupfuls. What else? The Chef helped out his students a bit: pebbles are fine, but what are they?

Silicon, calcium, to name a couple—so we add a source of these: sand. Then, iron, and magnesium—two more known comet constituents. Source? Dirt! Dirt can contain these, among other things.

For the carbon in our comet, we added—carbon: black charcoal dust; just a dusting.

There is nitrogen mixed up in comets too, so we had to add some to our concoction. Our nitrogen source (other than all the gaseous nitrogen floating about us in the air) is ammonia—NH₃ (what's a little hydrogen in the compound, more or less? In fact, ammonia itself has been detected in comets, so our recipe is true).

Organic compounds—carbon based organic molecules—have also been detected in comets…so we add a couple glugs of corn syrup. Okay, that's cheating a bit, because comet organics aren't known to come from agricultural products….

And lastly, but not leastly, is the two-in-one ingredient: contained in a plastic bag, I had the class use mallets to pulverize a few cupfuls of dry ice pellets into a fine powder. This adds not only the carbon dioxide to the material makeup of the Personal Comet, but that which really makes the difference between a bowlful of slightly sweet mud and the astral nugget of a comet: COLD! Space is cold, and so is dry ice.
In goes the frigid, dry frost, and out erupts clouds of billowing vapor—very exciting stuff. Now the Chef had to work fast, stirring and mixing and shaking the brew, and then squeezing the convulsive mixture in its plastic bag, with gloved hands, into a hard, solid lump. It takes a lot of squeezing, as it turns out….

Is it done yet?

I pulled out of the bag our Personal Comet, holding it out for the kids to marvel at—and they did. The double-fist-sized, dirty whitish, somewhat gritty hard blob is covered with pits and knobs and spouting plumes vapor. And, magically, it looks almost identical to a photograph of the nucleus of comet Wild 2, taken by NASA's Stardust spacecraft some years ago.

Everyone got to touch the comet—quickly, because it was quite cold—and make a personal connection with a tiny piece of the heavens. Now, I think, these kids are armed with an experience that will make their first comet-observing experience (yet to come for many of them!) a bit deeper, as I hope when they do see the vastly awesome sight in the sky, or through the eyepiece of a telescope, they'll also remember what it's like to touch a comet, or smell a comet, or see one spouting vapor right before them, in the palm of their hand….

Perhaps no single development of the last century has been more influential or more important than the laser.

The concept of discovery is a powerful sentiment in science. Television’s Discovery Channel and print journalism’s Discover Magazine have folded the word into their identities, and as a child that my iconic scientist was a paleontologist, literally unearthing discoveries of the prehistoric wilderness. Just as motivating, however, is the concept of invention, and perhaps no single development of the last century has been more influential or more important than the laser. In 2010 the laser turns 50, and to celebrate, a group of organizations including the American Physical Society, the Optical Society, SPIE and IEEE Photonics Society have organized a year-long series of events this year dubbed LaserFest.

UC Berkeley has been celebrating LaserFest this past week with special exhibits and events over the weekend at the Lawrence Hall of Science, and a special lecture on Monday the 25th by Roger Falcone, Bob Byer, and Nobel laureate Charles Townes, also at the Lawrence Hall of Science.

Theodore Maiman built the first laser out of a rod of pink ruby in 1960. However, the laser’s precursor and underlying principle belongs to Townes. In 1954, he and colleagues constructed the ammonia maser, a stunning proof-of-principle device demonstrating that intense beams of light within a narrow color range could be produced. A flurry of excitement and research efforts followed aimed primarily at developing masers that could work at higher and higher frequencies of light.

As maser research matured the name changed as well. A high-frequency MASER (the acronym stands for microwave amplification by stimulated emission of radiation) became the optical MASER. Then at a conference in 1959, Gordon Gould coined it as the LASER. (The L stands for light.) One of the conference’s organizers, Arthur Schawlow, rebutted that these new devices would be more important as oscillators rather than amplifiers, so perhaps they should really be calling it the LOSER (see the recent article in Physics Today). Curiously, substituting the O never caught on.

The laser’s influence in science and society, however, has been dramatic. We use lasers to read our hard drives and play DVDs. We use them to improve our vision. Lasers play an integral role in security systems. They are a crucial component of our ability to keep time accurately. The world’s biggest laser in Livermore could be on the verge of igniting fusion reactions. We even shot a laser at the moon, waited for it to bounce back, and used the information to calculate the moon’s distance to the Earth with unprecedented accuracy.

Time will tell what the laser’s future applications might be. Personally, I am rooting for a sign of extraterrestrial life from the SETI optical telescope. The research collaboration’s website says that “A tightly focused light beam, such as a laser, can be 10 times as bright as the Sun and be easily observed from enormous distances.” Then again, if the aliens do decide to shoot a message our way via laser, let’s just hope that that they don’t decide to crank up the power so high that we all get vaporized.

The particulate from diesel trucks, which contains a number of carcinogenic compounds, can also cause lung cancer.

Wondering how much soot is in your city's air right now? Find out through the Bay Area Air Quality Management District.

As I write this, it's rainy outside, which is a good thing from an air quality perspective. Rain keeps the dust, or particulate matter (that's "PM" in air quality jargon), glued to streets and cars, and out of the air. Here in San Francisco, our PM 2.5 value is seven — seven micrograms of soot for each cubic meter of air. That's pretty clean, so breathe deep.

Using the calendar on the left side of the page, check out the levels from January 8th — a day where the average PM 2.5 level was 52 — and you can see why the Bay Area Air Quality Management District declared January 8 a Spare the Air Day.

So what do these numbers mean?

PM 2.5 refers to the smallest soot particles that air officials measure – each particle is about 1/70th the width of a human hair. These particles are so small, they're invisible to the naked eye. They're small enough to travel deep into the delicate alveoli, or air sacs, in our lungs, where they can cause or exacerbate asthma and other breathing problems. From there, they can make their way into our bloodstream, leading to heart attacks and strokes. The particulate from diesel trucks, which contains a number of carcinogenic compounds, can also cause lung cancer. (Check out this excellent Q&A on the hazards of diesel soot.)

The black numbers describe the current level. Blue and red figures describe the change from that same hour, the day before.

When you look at the chart, check out the PM numbers for West Oakland, right next to the Port of Oakland. These are what air officials point to when asked to justify the new rules for Port truckers, which this story, and this one, describe. A few years ago, the BAAQMD conducted a detailed health assessment of West Oakland residents, finding cancer rates three times the Bay Area average. In this week's radio story, we also cite a 2008 Harvard study on lung cancer rates in truckers. Here's a story about the study, and the study itself.

Poke around the QUEST website a bit and you'll find an abundance of media on this subject. Start with Gabriela Quiros's terrific TV story, "Perilous Diesel." Gabi's also taken a closer look at some of the mysteries surrounding childhood asthma in another TV piece, "Asthma: What Brought on the Epidemic?"

Last but not least, here's a slide show of scenes from this week's radio QUEST story, featuring characters and scenes from several sides of the campaign to reduce diesel soot.

Listen to Truckers Clean Up Their Act radio report online.

One of the most amazing aspects of the cuttlefish is their skin. The skin contains up to 200 pigment cells per square millimeter that enables it to change its camouflage at will.

I have been working for the California Academy of Sciences for five years now this month. I have always held a fondness for the aquarium. On my first day of work, I took a tour with other new hires through the aquarium at Howard Street. We stopped at the giant sea bass’s tank. It was feeding time and we were given sardines to feed him. We were instructed by one of the biologists to hold the fish in two fingers just beneath the surface to let him suck the fish into his mouth. When it was my turn, I dutifully held the fish under the water and watched the huge fish round the tank and head my way. He approached quicker than I had anticipated and I got spooked. So I lifted the fish out of the water. Well he still sucked the fish up; but he also sprayed me with salt water and fish guts. So I started at the office, dripping in salt water and smelling of sardines.

Tonight after work, I descended down into the Steinhart Aquarium. It’s kind of an after-work tradition to tour the aquarium before heading home. I like to stop by and see the same giant sea bass that drenched me and the octopus next door when the lights have been dimmed and the halls are empty. I now often stop at the dwarf cuttlefish tank. Tonight, one of them was swimming around the top of the tank, shimmering in a varied and beautiful color display. The other dwarf cuttlefish was resting at the bottom of the tank, expertly matching the rocks around it.

One of the most amazing aspects of the cuttlefish is their skin. The skin contains up to 200 pigment cells per square millimeter that enables it to change its camouflage at will. It also has muscles in its skin that enable it to change its skin from smooth to rough. Different species of cuttlefish can change the color and texture of their skin to blend in with the environment around them, display spikes and bright colors to ward off predators, or even create a strobe color display to mesmerize prey.

As well, cuttlefish, part of the Cephalopoda family that includes squids and octopi, have one of the largest brain to body ratios of any invertebrate. They can take in input from sight, smell and sound in the form of pressure waves felt through their lateral lines. The reaction of color displays has demonstrated problem solving and biologists study them to learn more about invertebrate and possibly human intelligence.

I now keep a closer watch on this tank, in hope of seeing the new generation of dwarf cuttlefish. The Academy is the first aquarium in the US to have a captive breeding program for dwarf cuttlefish, Sepia bandensis. The program, launched by Academy biologist Richard Ross offers the Steinhart Aquarium and other institutions the chance to feature a species, which is both captivating and less resource-intensive to keep than larger cuttlefish species. Dwarf cuttlefish span only two to four inches in length. “By establishing a stable breeding population,” Ross notes, “our hope is to make it easier for aquariums to showcase cuttlefish and their remarkable characteristics without impacting wild populations.” It’s no wonder that traveling through the Aquarium has become my favorite part of the day. Even after five years of wandering, I still see something amazing with every visit.

For some great footage of cuttlefish in the wild, along with information about research on cuttlefish and an overview of their anatomy – visit this great site provided by NOVA.