spark

summer science #1: a hexing problem

 

Earlier this summer, Reese presented me with four research questions, which I noted on the handy dandy dry erase board that hangs in our downstairs hall. The questions are:

1. Why do bees make honeycomb in a hexagonal shape?

2. What is on the dark side of the moon?

3. Are there any unknown species of creatures on Mars?

4. Is there water on Mars?

We then proceeded NOT to research these questions until well into the summer, when I found a great article, "What Is It About Bees and Hexagons?" by Robert Krulwich, whom you might know as half of the RadioLab team of hosts. 

Robert Krulwich/NPR

In addition to some really freakin' cute sketches of bees making honeycomb in a variety of shapes, the article provides some fascinating historical background on the history of this question (trust Reese, our family philospher, to ask a 2,000-plus-year-old question).  After I digested the article, I walked Reese and Xander through it. They're visual like their mama, though, and wanted video. Voila: ask and the BBC + YouTube shall provide: 

Boiled down, we can see hexagonal comb structure as an engineering solution to the following three problems:

1. for the sake of efficiency, the structure must be something that can be built simultaneously by many bees at once (rather than one bee building one cell at a time)
2. wax is expensive - each bee must consume at least 8 oz of honey to produce 1 oz of wax - so the structure must use as little wax as possible
3. with the wax used, the bees must maximize cell volume in order to provide space for honey storage and growing bee larvae/pupae

In order to solve these problems, comb must be:

• composed of cells of identical shape (standardized shape = many bees can work at once)

=> this means shapeless blobs and custom-built cells are out

• structured in such a way that the sides of the cells are all the same length (more standardization)

=> so equilateral shapes must be used; no trapezoids or right triangles here.

• shaped in such a way that there are no gaps between cells (gaps would take more wax to fill)

=> so shapes like pentagons are out, since they can't be tesselated without gaps. This leaves us squares, equilateral triangles, and perfect (equilateral) hexagons.

• shaped in such a way that each cell has maximal volume while using minimal wax

=> hexagons win!

 

BONUS RESEARCH:

Watching the video above raised some additional questions for us. Reese was very interested in the differences between brood comb and honeycomb, and wondered why the worker bees feed the larvae early on but later stop and seal them up inside the brood comb. We realized we didn't really know much about the life cycle of bees, with regard to what the stages are and what each stage looks like. 

Check it out: 

via The Robinson Library

Arkive.org provided us with a great video showing a queen laying eggs, a view of eggs in otherwise-empty brood comb, workers feeding larvae (along with one bee doing a waggle dance), and finally mature bees nibbling and wiggling their way out of the brood comb. 

We are now all stoked about bees. I was already considering the possibility of adding a top-bar hive to our yard in spring 2015. In the meantime, we'll be living vicariously through beekeepers like McCartney Taylor, whose OutOfABlueSky swarm recovery videos are pretty awesome. 

What's your favorite bee video or bit of bee trivia? 

 

related posts:

let's find out: chestnut worms

fabulously lousy

let's find out: chestnut worms

In which we wake up one morning to discover that we waited to long to roast the chestnuts we harvested. What are these white grubs? What kind of insects will they grow up to be? 

It turns out they're the larvae of the chestnut weevil, probably either Curculio elephas or Curculio sayi. The female weevil lays eggs on the young chestnuts about 3 or 4 weeks before they ripen and fall from the tree. After they fall, the grubs emerge and dig down into the soil, where they will stay for a couple of years before reaching their adult form and starting the cycle all over again. 

I had wanted to know if there's any way to tell whether grubs are in chestnuts before they emerge - that is, how do I know that nuts are safe (i.e., bug-free) to eat? The answer: you don't know. If you want to minimize the chances of a delicious grub snack, collect nuts quickly after they fall and boil them for 20 minutes in order to kill the bugs (which will hopefully be too small to notice). Then freeze for later or roast and eat. 

If you can handle seeing some grubs, love some buggy science, and want to know what "curculio" means and how it connects these bugs to both ancient Roman theater and Jake and Maggie Gyllenhaal, check out the video!

(If there's anything I love in the world, it's learning something, documenting it, and then sharing it with other people. Hooray for the power of photography in the education process!)

fabulously lousy

Summer Science #1: a hexing problem

electric beat: scientific observations of the 5-year-old mind

Begging your forgiveness for the vertical video, I present a little 5-year-old scientific hypothesizing. Xander was playing the drums in our basement (note to self: get this kid some lessons, he is probably the most musical one of the bunch) and noticed the effect that his playing had on a nearby fluorescent bulb. The results are captured in the video clip above.

Age 5-6 is particularly interesting for its unique mix of the magical thinking of early childhood with the stronger logic that sets in after the "age of reason" (age 7-8). Kids at this age know a lot about very basic biology and physics, but give explanations for natural phenomena that reveal that they haven't quite connected all the dots yet, and rely heavily on imagination in order to understand the world. When my eldest was this age, I probably would have supplied the real explanation for the flickering light. Now, I generally hold myself back, having seen how kids can take their hypotheses to fascinating conclusions, and how they bounce ideas off of each other in order to form a more complete understanding of their environment. So when Xander suggested that our drum kit somehow stores electrical energy (bet you didn't know that!), I sat back and simply reflected his ideas back at him. He clearly knows that his drumming is somehow causing more energy to be supplied to the bulb, causing the flicker. What he hasn't figured out yet is why banging on a drum might have that effect. The simplest explanation for him is that these things are directly related to each other.

We showed the video to Griffin and Reese, who immediately said "he's wrong!", in a shutting-things-down manner reminiscent of Dana Carvey's John McLaughlin. I prefer not to throw about the W word, knowing that it rarely leads to productive discussion and often leads to fighting. I redirected: "it sounds like you guys have other ideas about why the light flickered."

Griffin stepped up: "I think the vibrations are making the light move and more electricity flow."

Me: "how does the drum make that happen?"

Griffin: "the sound waves vibrate the light, and when it moves, more electricity can flow."

Griff's idea was that the light wasn't sitting properly in its fittings, and when the sound from the drums vibrated it, it moved so that it had better contact with the electrical supply. Reese agreed with this hypothesis. Xander maintained that no, the drums themselves store and release energy. I'm wondering if the three of them will discuss this further in the future, and if they'll figure out ways to test their hypotheses. How does one determine whether or not a drum stores electricity?

fabulously lousy

Supposedly 1 in 10 school children catch head lice at some point in their educational career. I managed to play those odds and win during my own childnood - I don't even remember any outbreaks in my classes - but ever since my kids started school, I've been waiting for our turn to come. I knew a preschool family in which every member caught the bugs and had a horrible time getting rid of them. During our two years of public school, I received state-mandated lice alerts concerning cases in the school, but they appeared not to be in my kid's classroom, and we were spared. 

Then came the infestation of 2011-2012. Oh, my goodness. The bugs started in the 3rd or 4th grade (my eldest is a 3rd grader) and would. not. go. away. For a while, it looked like we were ok, but on the advice of a fellow 3rd grade parent, I bought the uber-awesome Nit-Free Terminator lice comb, wet my boy's super-thick hair down, sprayed it with conditioner, and went to work. I wasn't really sure what I was looking for and expected eggs to look like little white dots, and the bugs to look like fleas, perhaps. I had noticed one or two grains of dirt on his scalp that looked unusual, but they didn't look like what I imagined a nit to look like. A couple of them came off in the comb, and I wiped them onto a white cloth. Was it dirt? It looked like dirt. It didn't look like a bug. I took a photo using my macro lens, zoomed waaayyyyy in, and there, on the LCD screen, was something that looked like this:

No bigger than a comma in real life. A dot with a tail. And suddenly, looking at this thing on the back of the camera, I got it. Ohhhh, that's what I'm looking for. THAT's a nit. 

I found a few more of them, as well as one or two crawly full-grown lice:

The bug was tiny. Smaller than a flea. Barely bigger than the nits. I took some tape and picked the lice and nits up off of my cloth, then sealed them to a piece of paper, so I could get a photo. 

We got lucky, and after the second day of combing (we combed every day for two weeks) there were no more on his head, and they didn't come back. None of the rest of us were infested, probably because we caught it early. THANK GOODNESS. The third and fourth grades continued to battle the bugs for over a month, and finally, all was calm.

Or was it?

Reports started coming in from the kindergarten in late April. Oh no! I checked Reese's head, didn't see anything worth worrying about, and left it at that. Foolish woman. Didn't I remember that you don't see them until you use the nit comb on wet hair? One night at bedtime I did another check, and noticed a speck of dirt on Reese's nape, then another the same shape and size as the first. Hmmm. Time for the comb. I wet him down, ran the comb through, wiped the comb, checked the cloth. Nits? Took a photo, blew it up. Yeah, nits. Here we go again.  

It was 8pm when I found the nits, 9 when the poor combed-through kid finally got to bed. I kept him home the next morning, and asked him if he'd like to look at his nits under our microscope. While I was getting the little buggers into focus, I made several totally awesome discoveries. First, some of those nits were actually hatched lice, not eggs. Second, they were smaller than the lice I'd seen before, with different proportions and softer curves. This is why I thought they were nits. It turns out they're nymphs, a young form of the louse. Finally, and most awesome of all, one of the nymphs was still alive under the cellophane tape...and I could see its digestive system working! It occurred to me that the telephoto lens of my point-and-shoot camera might fit into the eyepiece of the scope - and it did, perfectly - and I caught the awesomeness on video:

Way. Cool. I love how you can see the tiny latch-like pincers flexing. Seeing them, you can understand why lice are so hard to get out of hair. Those legs are built to grab on and hang on. The stuff gurling in the louse's digestive system is its most recent meal - i.e., Reese's blood. Some people have asked questions about the blue filaments - they are not human hair. They are lint/fuzz that stuck to the tape when I picked up the louse off the cloth wipe.

you know they would totally wear Groucho glasses if only they came in small-enough sizes

Because I was so thoroughly geeked-out, I called up the kindergarten teacher to ask if she would like me to bring the louse, the nits, the microscope, and the video to school when I came by to pick up preschoolers, so that I could show the class. Many of the kids had had lice, but the bugs were still fairly mysterious to most of them. An insect that's hard to distinguish from specks of dirt and lint is a little difficult to visualize and understand. 

There are probably not many schools who would be open to allowing a parent to bring in live lice for show-and-tell, much less be excited about it, and this is just one of the many reasons why I adore my kids' school. The teachers had set aside a space in their "studio" room so that three students at a time could come and take a look and ask questions. Virtually every child was fascinated as they watched the video and took a look through the microscope and another small magnifier. Several parents who have both preschool and kindergarten children also came by, curious to know what a nit looks like - how big is it, really? I was glad I had brought the paper with taped-down nits, so that they could see what we're all looking for when we comb and comb and comb through our kids' hair:

That photo is about two times as big as life-size. Nits are TINY. They're specks. The hatched bugs are tiny, too - there are two in that photo. Can you find them? 

I was SO in my element - I love nature, I love discoveries, and I love teaching. Science is cool, man. And now I'm bringing all this good stuff to you, in case you've ever wondered what a nit looks like, or how a louse's feet work. They're really incredible insects. I'm glad a couple of days' worth of combing took care of them again, and that we didn't have any repeats, and that the kindergarten class kicked the infestation much faster than the 3rd and 4th grades did...but if you have to deal with parasites, you can at least enjoy it a little and learn something new and fascinating. 

the awe of atheism

When people get going about how atheism is so cold and heartless, without beauty or mystery or wonder, I always wonder how they can know me (I'm all about beauty and mystery and wonder!) and think this is true. I find far more joy in learning WHY the world works the way it does than explaining it away with "God made it that way." And the absence of belief in heaven has actually made my life richer and more meaningful.

 

Photo source: help me track the original down so I can give the photographer credit! Photoshopped quote and earth by Reddit user JesusClausIsReal. Quote from speech delivered to Harvard Humanist Society, April 2010, by Adam Savage - full text here.

violet jelly, part 2: color comparison

We recently made our first foray into making jelly from flowers, and the results were tasty. We used a natural unbleached sugar for the first batch, and I had wondered ahead of time if it might affect the final color of the jelly. We ended up with a reddish product instead of the bright violet shown in the recipe. I resolved to find more violets, buy some white sugar, and test out my hypothesis.

I knew I needed a better source of blossoms and thought of a friend who had complained that his back yard is overrun with them. I know these friends don't use chemical fertilizers, weed killers, or pesticides, so I took a peek - oh my, violet lushness! I asked permission, then picked and picked and picked to my heart's delight. Four-plus cups of flowers later their yard was still glorious with spring color and I had enough violets to make not just jelly, but also maybe try out some natural egg dying.

After steeping, sugaring, boiling, and canning, here's the final color comparison:

The first batch, with a more reddish color, is on the right. The two jars on the left are the new batch. Does sugar affect your final color? Absolutely! 

So now the question is: how important to health is the use of natural, unbleached sugar? Which jelly would you rather eat, the brighter one, or the one made using a less refined sweetener?

perigee supermoon

I missed moonrise, but couldn't resist a once-in-twenty-years opportunity to capture last night's full moon at perigee (the closest point of the moon's orbit around the earth).

When I was in 7th grade, my science teacher, Mr. Linville, shared with us that he doesn't see a man in the moon, he sees a rabbit in the moon. Ever since then I've smiled when I see the rabbit. Its ears are the Sea of Fecundity and Sea of Nectar. Its body is the Sea of Rains and the Known Sea on either side of Crater Copernicus. Its powderpuff tail is Crater Tycho. It crouches on its legs, the Ocean of Storms. (I like this simple, interactive moon map.)

Can you see the rabbit? 

the mystery of the emerald elixir

Last night the water in this sunbutter jar, which had been left to soak in the sink, was discovered to be a dark bluish green. Dan asked if we had washed paintbrushes in the sink. We had been out for most of the day and no art supplies had been used at home, that I could think of. It didn't make any sense that soaking the jar would turn the water green, but determined to see if it would happen again, I emptied the water, filled the jar with fresh water, and added a squirt of soap, just as I had the night before. It's not as dark as yesterday, but the water is definitely greenish. 

These accidental discoveries are one of my favorite things.  I feel compelled to get to the bottom of the mystery.  Had the sunbutter (a spread similar in consistency to peanut butter, made from sunflower seeds) reacted to the dish soap? Was the soap a red herring, did immersion in water cause some kind of oxidation reaction? 

It turns out that sunbutter is known for its odd propensity to turn cookies green when it's used in a recipe.  The solution to this problem (if indeed you consider it to be a problem; I consider it to be awesome) is to add lemon juice and/or reduce the baking soda or baking powder in a recipe.  

Photo via waffles-n-trees. Some find green cookies disturbing. I find them awesome.

It turns out this nifty effect is due to the presence of chlorogenic acid (C₁₆H₁₈O₉) in sunflower seeds.  If you go back to your high school chemistry, you might remember that acidity and basicity are measured using the pH scale; solutions with a pH less than 7 are considered to be acidic, solutions with a pH greater than 7 are considered to be basic or alkaline, and solutions with a pH of exactly 7 are described as neutral.  My internet research reveals that when chlorogenic acid is added to an alkaline solution and the solution is exposed to air, the solution turns a bluish green color.  

Guess what's alkaline? Soap. And remember my acid-base reaction vs. oxidation hypotheses? Turns out it's really kindof both.

I shared my observations with Griffin, who had also noticed the blue-green water the previous day. Before hearing my hypotheses, he understood why I had attempted to replicate the previous day's conditions and suggested that the water today was less vividly green because there was less sunbutter residue inside the jar.  He also suggested testing my hypotheses with two jars - one containing only water and one containing soap and water.  I immediately felt like a fool.  With a dual hypothesis, why hadn't I attempted to test them both? I posed the one-jar problem to Griff: how can I run two tests when I only have one used-up jar of sunbutter? His solution: try with water first, then add soap if the color hasn't changed after a certain amount of time.  We agreed that one day was an appropriate amount of time, since an obvious change had occurred in both of my batches of water after 24 hours.  

Now we're itching to test out our evolving hypotheses, and have determined that we can run a more scientifically rigorous study if we purchase new sunbutter, place identical portions of sunbutter in multiple identically-sized jars filled with a specific amount of water, then subject each jar to slightly different conditions so that we can determine which factors contribute significantly to the color change. I was pleasantly surprised that Griff could come up with various study conditions on his own and demonstrated an understanding of hypotheses, hypothesis testing, and study controls.  The conditions we decided upon include:

1. sunbutter/water without lid
2. sunbutter/water/soap without lid
3. sunbutter/water with lid
4. sunbutter/water/soap without lid

I also shared the green cookie conundrum with Griff and told him about the effects of adding lemon juice or cutting down the baking soda.  He proposed two additional conditions:

5. sunbutter/water/soap 
6. sunbutter/water/soap/lemon juice

We could, of course, do each of those with and without a lid, too, yielding 8 total study conditions. What's more, we could also design conditions with and without the addition of another base, such as baking soda.  I think adding that level would bring us to 16 conditions, which feels overwhelming to me, so perhaps for the first round, we'll stop with lemon juice.

This is very exciting.  My favorite discoveries - and the ones that stick with me the most - are those I stumble upon like this.  Can you tell the sex of a butterfly from its chrysalis? How can you see a slug's internal organs without killing the slug? How do slugs breathe? What are nasal conchae shaped like? What are those funny moving bits of sticks on the bottom of a stream? How do ladybugs develop? What is that orange thing on a swallowtail caterpillar's head? The answers to all of these, the journeys that led to them, and more are in the science catergory of this blog.  Science is so cool.

sunday brunch

A collection of interesting, fun, and/or thought-provoking things I encountered this week.

First, a shameless plug: I'm one month into a new 365 project.  What I learned from my last one was that I needed a more spontaneous, lighthearted assignment this year.  So I give you Play by Play, a 365 project inspired by my love of silly toy photography.  It kicked off with a week of Swiper the fox in the Dominican Republic (I love Swiper and he's easy to tuck into a camera bag while traveling), and I've stuck with my canine friend ever since.  That's him in the photo at the top of this post, having a sail on a rainy day.

Which reminds me of a John Stuart Mill quote shared by Terry Border today: "That so few now dare to be eccentric marks the chief danger of our time."  So when I'm baffling neighbors by lying in the street taking pictures of toys floating in puddles in origami boats, I'm doing a public service.  

Public-service-wise, if you feel like being slightly less eccentric but still spreading some love, check out Kind Over Matter's printable free compliments and free positive thoughts sheets.  Fun! Maybe leave one on the community board in your coffeehouse or school?

Via Kind Over Matter's Friday Lovelies, I found this wonderful "warning" about self-portraiture.  It reminded me of my friend Heather, who is doing a self-portrait 365 project this year.  Also on the 365 front, there's a new Facebook group for 365 artists.  

I was reminded of Kind over Matter by her appearance on RecycleArt.  I wouldn't necessarily define all of the projects there as "recycled" - for example, using new pencils as sculptural materials - and some of it isn't exactly art - like these compost bins - but there's something for everybody.  I was called to check out the Simple Science demonstrations from Linda Dong.  Knowledge can (and should?) be elegant!

Just like I do every January in Virginia, I'm wishing the weather would commit to either icy/snowy or sunny/springy.  We go from scraping windshields to prepping the garden in the same day.  I've recently spent two afternoons cleaning up our flower beds and veggie garden, organizing the garage, refilling bird feeders, pruning shrubs, and generally getting into a springtime mood.  I'm ordering new Mud Gloves and a sieve for our compost.  I'm also telling myself NO MORE STICKS OR APPLE STICKERS in the bin.  We're lazy composters and never turn the darn thing, and those plus corncobs and unbroken eggshells make it to the bottom relatively intact.  Everything else has turned into beautiful moist humus, which I'm using to mulch the garden.  I'll eventually turn it under.  The warm weather has me thinking about seeds and pea fences and getting rid of some of the shrubs in the yard so that I can plant a dogwood and have a nice bench or two for reading on lovely spring afternoons.  

On colder afternoons, when I'm not taking pictures of ice, I'm enjoying a little Lenka, whose tunes I discovered thanks to Jason and Wendy Ward of Ward Photography.  

Photography leads me to remember to share that HandsOn Greater Richmond has a call out for photographers to document their community efforts.  I've signed on to volunteer and plan to choose one or two events a month.  

Photo lovers and science geeks and fans everywhere of beauty might enjoy this six-month-long exposure made by pinhole photographer Justin Quinnell.  

And finally, a beautiful thing you can create - Silk, a nifty interactive piece of fun that I learned about via my lovely friend Lynz, who always links to great stuff.  

Finally, while my back yard is lovely and ice is pretty, I've been wishing to be back on Sanibel Island lately.  I've had at least five or six recent dreams about shell collecting! Where do you want to be right now?

gone but not forgotten

I knew this would happen; I build up a head of steam about something big, have too many things to say about it in too little time, stop to think a while, and while thinking, life takes over.  And so here I am, washing a skull in my sink, and not writing about Esfuerzo.  

I promise I'll get back to Esfuerzo soonish.  But right now, I'm knee-deep in learning whitetail deer anatomy, examining dentition, finally understanding nasal conchae.  This skull came from Larus Park, where a friend and I found it hanging on a tree.  

A find like this is too much for me to pass up.  It must be examined, shared.  But as with everything else, it has to pass my ethics review. While I typically adhere to the "take only pictures, leave only footprints" axiom, the fact is that some elements of nature do end up being removed for educational purposes by rangers, geologists, biologists, and the like.  When should something be left behind, and when is it ok to remove it?  In this case, the skull was not in a National or State Park, it is not an essential part of the ecology, and it is not rare/endangered.  My intents were educational, for both personal and school use (I have already discussed it with both the school director and the art teacher).  I decided that the benefits outweighed the costs, and I headed back to pick it up. 

Our initial assumption was that the skull, which is missing the mandible, belonged to a deer.  Examination and comparison to images of other whitetail deer skulls confirmed this.  

A taxidermy review suggested that a peroxide soak would be best for cleaning/bleaching the bones.  This removed loose debris and also made me feel like the bones were less likely to harbor contagion, although honestly, this skull is old enough that it probably hosts nothing more than the average rock or stick would.  Dan pointed out the issue of prion disease, but without actually consuming venison, I'm not convinced there's much risk.   I'm maintaining handwashing protocols, though.  

The peroxide didn't do much to improve the appearance of the bones.  The teeth were especially bad. I set to work with dish soap, Barkeeper's Friend (oxalic acid), a toothbrush, a safety pin, and a sewing needle.  The teeth look better, if still somewhat less than gorgeous, and I have a newfound appreciation for the work of dental hygienists.  I'm also reminded that I need to schedule cleanings for my family.

I also have a new appreciation of nasal anatomy.  This is a view from the anterior aspect of the nose, looking up through the nasal cavity.  The skull is lit from beneath/within by a desk lamp.  At midline is the septum.  The turbinates curling on either side are the conchae.  I've never been able to picture this when looking at sagittal sections of human conchae.  

The skull has also already afforded another unexpected treat: this little hitchhiker:

He was pretty cold and slow when I discovered him yesterday, and died overnight.  I've tentatively identified him as a juniper stinkbug, Banasa euchlora.  It's worth noting that the tree in the first picture of this post is a Virginia cedar, Juniperus virginiana. 

You can also get another glimpse of the stinkbug here, at my new 365 project.