Last week I introduced a group of young people to a new world of wonder. It has been a short time since I noticed doing that, but in reality I have enjoyed a lifetime of “new world” introductions. You see, I spent the majority of my life (so far,) as a biology teacher. Though I retired from the high school classroom 4 years ago, I still teach. Sometimes I teach groups of students that visit the Lake Metroparks Environmental Learning Center (that is in Lake County in northern Ohio.) Sometimes I teach my granddaughter Maddie, and sometimes I simply teach people that happen to be standing next to me. But this week I was reminded of how exciting it can be to learn too. I work with a group of third through fifth grade honors or gifted students from a local school district. I guess they are “gifted” because they have been tested and identified as “cognitively gifted,” but I think they are gifted because they show up every Tuesday afternoon, after a full day of school, with notebook in one hand, snack in one hand, camera in one hand, and usually some other artifact in one hand. They accomplish this because they are third through fifth graders, they have an almost unmeasureable amount of energy, they are gifted, AND they are curious!! This week I gave them access to the microscope. This week I gave them access to new worlds. Their energy, and their curiosity did not disappoint. I decided to start their adventure with some microscope basics. I wanted them to appreciate how special this exploration tool is. I wanted their journey to be less frustrating and more successful. I wanted them to be able to see and to measure with the microscope. They were ready, willing and very able to explore new worlds. The world I introduced them to was an import from my small, backyard pond. As I left for the Environmental Learning Center I stopped and collected a bagful of pond water and a few handfuls of hair-like filamentous algae. The major genera in my pond is *Cladophora. (Sometimes called “pond scum,” but I prefer Cladophora.) My favorite thing to see in pond samples is, in fact the alga types. I love the green color and the ability to see into the cellular landscape. I love seeing the intercellular spaces and the dots of color in the chloroplasts. I love trying to “notice” the nucleus in the cell. I say “notice” because that is what you do when you start a journey into the microscopic world. Often the new adventurer will fail to notice what is clearly there. “Can I get a new sample?” “There isn’t anything in mine!”. I go over to take a look at this “empty” field of view. “Wow!” I scream. “Look at this!”. I tend to “notice” more stuff. Of course I see the algae. I describe the cellular boundaries, the cell walls, the membrane, the chloroplasts, the nucleus (if lucky and the lighting just right.) Then I look beyond the strands of algae and “notice” the hundreds or thousands of euglena scooting around the filaments. They are small. We have the 10X objective employed, but visible if only you are willing to “notice.” occasionally a much bigger paramecium swims by. I go crazy! By this time the young explorer wants her microscope back. They want to “notice” what’s on the slide too. New worlds, new wonders! Then we load up the slide with some daphnia. Daphnia is what these scientists want. They are big enough to be easily observed.

They are complex enough to look like real pond monsters. Daphnia are small microscopic crustaceans. They have a heart, gills, a digestive system, an eye spot AND they are “see-through.”. Perfect for a young scientist to get excited by this new world. They can see something happening. Thirty-four years teaching biology, four years of undergrad biology classes, two classes of biology in high school, and I still get goofy when I see a captured daphnia on it’s side, heart pumping, gills waving, food moving through the intestines, living its little life on the microscope slide for all to see.

No wonder the mini-explorers get so excited! As a special treat , we gave each of the little scientists their very own “daphnia-in-a-tube” to wear on a string around their neck and to take home. Their own new world, their own new wonder!

*Recently a discovery of a new use for this pesky pond clogger has been made. This web site discusses a possible use of the cellulose abundance of Cladophora. They may be harvested for use in new, efficient , paper batteries. They can come to my pond and harvest all they want. Check out this site. http://ceramics.org/ceramictechtoday/materials-innovations/green-algae-harnessed-to-make-paper-based-batteries/

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Location:Misty Ridge Dr,Painesville,United States

So here it is, Earth Day 2010. 40 years and counting. A lifetime for many and yet it seems like a blink of an eye. Forty years ago, Kent State University (12 days before it became “famous” worldwide,) a freshman bio major and ready to let my voice be heard. The first Earth Day was a big event on campus, at least in the biology building, Cunningham Hall. Senator Gaylord Nelson had proclaimed the first Earth Day and we were ready. Ready to march, ready to learn, ready to teach and ready to change this ailing planet. That really was a lifetime ago. Well, a career’s lifetime ago. Thirty-four years in the biology classroom. Thirty-four years with approximately 100 students a year (some years less, some more.) 3400 youngsters that learned about their world, our world, THE WORLD. 3400 young folks learning about where in the world they are and how they need to understand it and take care of it. Some years we all forgot about the health of our planet. Some years it was fashionable to care. So how are we doing now? Well, the planet is still ailing. We can make a list of the wounds, but suffice it to say that an extended
stay in the critical care ward is called for. But at least it is again fashionable to care about the health of the planet. The “Green” word is good right now. Actually it is profitable for businesses to be “Green.” Maybe that is the direction we needed to go. Not “It isn’t easy being green!” as my friend Kermit always said. Now we can say “It is easier being Green than it was before” and that is a good thing.

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I found a nice deep part of the river just beside the shallow riffle where I was standing.  The shale that makes up most of the river bottom in the Grand creates shelves and ledges in the river’s structure.  Some of the shelves or ledges create waterfalls, some create deep pools.  The pools provide sanctuary for the big fish as they make their way up or down stream.  Often, a large three or four-year old trout will be resting or logging in these pools.  Sometime more than one can be seen.  That is what I was watching (and casting to,) on this wonderfully warm weekday afternoon.  There were a few other fisherfolk around, but not many.  Most seemed to be fish-watching too.  Steelhead trout on their spawning run (both up stream and down,) are not really interested in eating.  Eating is what they have been doing all summer in the lake.  Occasionally they will attack a floating bug or nymph (as much from habit as from hunger,)  and that is what a Steelhead trout catcher is hoping for.  The particular large fish I was watching did not seem to want to attack anything other that other trout that happened by.  I nymphed, I egged, I streamered, but mostly I watched.  But that was ok.  What a scene I was watching.  The  fish I was “playing” with was probably a 3 year old (maybe 2 years since the size of a fish under water is a bit difficult to accurately estimate due to the tendency of water to magnify,) 24 inches or so and wonderful to observe.  As smaller fish entered the pool the “resident” cleared them out.  A short rest seemed to be fine, but only a short one.  If a smaller trout stayed too long, it was scooted away.  If too many smaller fish entered the pool, even a short stay was not allowed.  I was casting to the rest stop, but mostly I was watching the residents.  Occasionally I would hear a noisy splash behind me.  Not a big splash, but kind of a  splatter.  In fact, a series of splatters.  As I turned to see the cause of the noise I saw a younger fish making its way down the riffle.  Sometimes they start down a shallow section of the river instead of staying in the deeper runs.  When this happens they need to “skitter” along the gravel and rocky riffle areas.  This creates a splashing noise and is great to watch.  Of course, if I was really just trying to get fish I could simply net the skittering fish, but I was here to watch and appreciate as much as I was to catch fish.  And appreciate I did!  I have been watching the tremendous new television series on the discovery Channel.  This series called LIFE, is wonderful.  But I was IN this “Life” episode, so I just watched.  When I view the Discovery version of “LIFE” I am amazed. The photography is remarkable even if the narrator’s explanations leave a little to be desired (in the US version, Opera Winfrey is the narrator.)  I have found a few too many explanations of wonderful design as the reason for a particular animal’s shape, color, structure or success to be comfortable.  I’m not sure how Sir David Attenborough narrates, but I’m sure the BBC version discusses the evolutionary processes a bit more accurately.  But here I stand in the middle of  a river, watching my own episode of LIFE.  That’s what this essay is all about.  We all need to watch the episodes of LIFE all around us.  Whether the tapping of a pileated woodpecker, or the hunting of a red shouldered hawk, the hunting practice of Fitzroy (my cat,) or fledging of a house wren, LIFE is all around us.  Paying attention to the world around us is actually the theme of my Australian friend’s entire blog.  It is called “Paying Ready Attention” and can be found at http://payingreadyattention.blogspot.com.  This blog is deserving of a good long look, or rather many looks since Stewart adds to this site quite frequently and every entry is worth reading.

That is what I was doing last Thursday.  I was standing in the middle of a riffle, up-stream of  the confluence of Big Creek and the Grand River “paying ready attention.”  I’ll be back.  I will search out this pool.  I may ‘tease’ the resident for a short while.  I may try a nymph, or a streamer, maybe an egg pattern.   He  (or she) many not even be there, but I will certainly be paying ready attention to the LIFE around me.

Mole cricket tattoo

Most of us worry about the growing list of endangered species, many of us donate time or money to groups who work to protect them, but how many of us have taken steps to promote the cause by tattooing images of extinct organisms on our bodies?  I mean, really.  I ask you?

Well, 100 dedicated folks in Great Britain have.  That’s how seriously they’re taking it.  It started with a group called ExtInk and a November, 2009 exhibit of drawings, illustrating 100 of the most endangered species in the British Isles. Creatures like the water vole, the tundra swan, and narrow-leaved hellaborine.  It concluded with the live tattooing of the drawings on 100 willing volunteers. Apparently, you had to apply for the priveledge of having one of these tatoos (would love to read a few of those letters!).  Here’s the full list of all the participants, along with which tatoo they received.

I love the idea of these 100 people, walking around as bold biodiversity ambassadors.  Can’t you imagine the conversation?  ”What’s that on your arm?”  …”Oh, that?  Well, that’s a red-backed shrike.  Let me tell you about it…”

HelloTeachers,

Together with the Genetics Policy Institute, the University of Pennsylvania is seeking funding to develop a new and innovative Stem Cell education website and live classroom demonstration that will expand on Project BioEYES. For those teachers who are not yet involved with BioEYES, it is a live classroom experiment that uses zebrafish to teach students about cell biology, development, and genetics. It has reached over 18,000 students since 2002 and we hope to continue to offer new and exciting classroom opportunities.

This survey will help us gain insight into your interest and knowledge about how
to best develop online and classroom-based stem cells resources for teachers.

Please complete this survey so that you can have a voice in the project’s
development. We truly appreciate you taking the time to complete this! It will
only take a few minutes.

http://www.surveymonkey.com/s.aspx?sm=zf9lwefON6Im4_2bkWSs1jwQ_3d_3d

Sincerely,
The Project BioEYES team

She didn’t let me down this month when she interviewed Doug Emlen (University of Montana) who is an entomologist who studies dung beetles and has become an expert in insect weaponry.  Dr. Emlen described the creatures he studies and their amazing horns – so elaborate and intricate.  He walked Terry through a vivid description of the beetle’s turf battles and how they use their fancy armor to protect, defend, and establish sexual dominance.  His tales of collecting dung beetle specimens from around the world were entertaining and delightful.

Past Fresh Air episodes are all available online as podcasts.  Here is a link to the 40-minute interview with Emlen.  You can also find some amazing video of the dung beetles fighting.  And Dr. Emlen’s web  site includes a gallery of gorgeous photos of the beetles he studies.

This stuff is like biological bon bons.

Just a little observation I made last June—

What a day I had last Sunday. It was Father’s Day and the weather in Northeast Ohio was magnificent. I took the opportunity of a lazy afternoon to sit on my back porch and while listening to the music of WKSU (my local Public Radio station,) to read a new history of evolutionary thought that I had recently purchased. Evolution, the Remarkable History of a Scientific Theory by Edward Larson, it is called. Reading about the powerful arguments and discussions that resulted from Darwin’s 1859 publication of The Origin Of Species is always a pleasure for me. But especially when sitting in my back yard on a lazy afternoon. It is a wooded lot and I have had the pleasure of watching a nesting pair of house wrens all spring. Sunday was a special day for the House Wrens, and for my wife and I as well. It was a day that reminded me about being a teacher and also about being a parent. Sunday was the day that the young wrens first left the nesting bottle that had been their home for the past 15 days or so. Betsy first noticed them early in the morning. (I was out playing golf too early to even want to remember.) She told me that she saw four small wrens, First two then the next two. They were flitting around the garden. They would fly from the hanging nest bottle to the garden fence. Then to the branches just above the bottle, then back to the bottle. First two, then the other two. Then she said she saw the bigger “parent” birds leave the bottle for a while. By the time I got home the routine was being repeated over and over again, but by noon they were adventuring out much farther a field–to the split rail fence we have maybe 50 yards away–to the branches of more distant trees–then finally back to the nest. But as the afternoon wore on and I kept glancing up from my reading I noticed that there was a ruckus at the nest. The parent birds were not to be seen, but the young were still flying about. When they landed you could see them flutter their wings. Possibly getting feathers into place? Maybe getting used to the new skill of flight? Who knows? But I kind of thought that they were pretty amazed at this flying thing. Of course I was reading a book on the history of evolution, so I was really trying to be more scientific, more objective in my interpretations. Then I noticed what the commotion was at the nesting site. When the young landed and tried to get in there was a loud distress sound coming from the opening and the young bird would fly away. The noise was the same one I had been hearing for three weeks whenever I walked near the bottle, when I mowed the lawn or checked the holes in my garden fence that the local rabbits created when they breached the security of what I thought was an impenetrable barrier around my 5 tomato, four cucumber and 3 zucchini plants. But that’s another story for another time. This distress call was pretty effective. It got my attention and I tended to move away from the nest. Pretty much what was supposed to happen. But now it was being used for another reason. I was nowhere near the nest, only the returning young. I started to wonder about the sequence of steps in the raising of a young house wren, and since it was Father’s Day, in the raising of a young daughter or son (I’m a step-dad to two daughters, but I have an imagination.) Then I thought about being a teacher. It’s pretty much the same, and I have been doing that for 31 years now. I imagined the house wren parents’ thoughts.

“We have worked for almost a month to get to this day. We flew in to the yard, we scoped out the best nest site. We checked the big wooden apple that hangs in the Maple tree near the wooden fence. We looked at a nest we built two years ago in a bottle that is mounted on the shed and even looked at the new bottle on the other side of the shed. We found the hanging bottle that we used last year and started to “fix-it-up.” I added more twigs and some soft grass. Then I lined it with feathers from my own chest. That’s when I started to mark the territory. I marked it with sound. Calling out my bubbling, chatter song at each of the corners of the yard. I did this to attract the mate too of course. Since I had the best nest sites I guess the selection was rather easy. Nonetheless, we got down to the business of creating the new lives. We had four new eggs to care for and we did care for them. Every minute of every hour, one of us was there. Sitting-on or turning. Watching and protecting. Calling out when danger came near them trying to distract any intruders. We took turns getting food for one another and watching and turning and just waiting. The eggs hatched and that’s when the work started. Food, food, food. Both of us getting food for the chicks—four of them!!! Bringing it in and stuffing it into the biggest open mouths in the nest. Get food, fly in, stuff it in and then go get more food. For twelve to fifteen days. Soon we were also cleaning up. Fly in get the white fecal sack and take it out. We did not just drop it. That would make finding the chicks too easy. We flew it away and then dropped it. Fifteen days and then the day of flight came. We taught you to fly. We taught you to catch the winds and to land. We taught you how to look for insects, to feed yourself. Later in the day we started to repeat the song, the song for territory marking and for courting. We repeated it at the four corners of the yard. We sang it by the garden and by the big maple. But we also let you hear another sound. The distress sound. You heard it when you tried to return to the nest. You were tired from your lessons and wanted to come back to the nest. But we have given you gifts. We have taught you how to fly, how to hunt and how to sing. We have given you all the tools you will need to succeed, to survive. You can’t come back home now. That is what the distress sounds mean. Now you need to go out, to go out to find a new yard with your own wooden fence, your own maple tree, your own nest bottles and ultimately your own lives. This is the gift we gave you. We gave you knowledge, skills, tools. We were your parents and we were your teachers. Now you hear the distress sound when you return because you are ready to go off and be house wrens yourselves. Fly now, sing your songs.”

Of course I didn’t hear any of this conversation, but I’m sure it what was being said Sunday afternoon. It made me think about being a teacher (and a parent.) We work hard to get the site ready—the classroom, the unit, the lesson, the special project. We study, we prepare, we devise and we plan. Then we work to give the students the skills they will need to succeed and to survive. That’s what we do; we get them ready to survive. Sometimes they don’t want to leave, but they are ready. They can succeed and they move on to fly, to sing their songs, and we start all over again with a new brood the next season.

So I sit here and listen to the song lessons and to the distress sounds when the young birds try to get back in and I think about doing that for 31 years and then I smile.

It has really been 37 years, but I’m still smiling!!

Now for Part Two:

After the students build their own spreadsheet models of the hypothetical sparrow population, as a class we discuss the parameters that taken together determine population growth or decline.  I guide the discussion with questions until the students are able to articulate the four factors that determine population growth:  birth rate, death rate and migration (emmigration and immigration).  I am careful to make sure the discussion includes reviewing a working definition of a population and that the factors identified are rates and therefore have a time element to consider.  At this point we revisit the sparrow spreadsheet model and identify how these four parameters are taken into account in the actual cells of the spreadsheet.  Students quickly identify that there is no migration terms and that the birth rate is taken care of when each pair of sparrows produce 10 offspring (column D).  They have a more difficult time with the death rate.  There is no explicit cell with a death rate parameter but only the offspring in column D move to the next year–death is taken care of by omission.

The discussion then moves to asking the students to consolidate these four factors into one term–a per cent of increase or “r“.  We also establish a variable for the population size at any particular time interval: “N_t“.  The students are now challenged to represent the exponential population growth in a single equation with the variables “r” and “N_t“.

Eventually the class arrives at the following:

It’s now up to them to create the spreadsheet using the formula.  Interpreting normal algebraic notation into spreadsheet notation is a bit of a challenge but they usually figure it out.  By iterating the formula (using the results from one time interval as the basis for the next) the students can explore and create models that without computers would require a familiarity with calculus.  Once the students have created their simple model I have them expand it to 300 generations or time intervals and graph the results.  When trying this with your students make sure that you don’t get too explicit with your help—students have to work at building this model but it is doable for most.  You should try it as well before checking on the spreadsheet embedded here:

If the spreadsheet is not loading you can find it at: Exponential Model

There is one spreadsheet technique that you need to be aware of to make this model–the difference between relative reference and fixed reference in a cell’s formula. Since the reference to “r” always points to the same cell, it should not change. The default in a spreadsheet formula reference is “relative”, which changes. You can make a cell reference fixed by adding a dollar sign in front of both components of a cell’s address. For example referring to cell: B1 is a relative reference but referring to $B$1 is a fixed reference.

Normally when I explore this topic in my class, we can pretty easily get through the sparrow population model and the exponential model in one hour. Modeling is an additive process and this is only the start. Note that the procedure thus far has only added a bit of complexity at each step–with only rudimentary math operations. The next step will be to explore the logistic model. I try and reserve at least a day for it along with a homework assignment. I’ll cover the logistic in the next post.

BW

BW

I've found a new home!

All of a sudden we are starting to pay attention to living things in the world around us instead of the just the weather extremes.  So much happens in the world of biology this time of year it is really difficult to pay attention to everything at once.  In the classroom however, the feeling seems to be that the year is winding down.  The “State Tests” are either over or almost over (this is the main indicator of the end of the year for some curriculum directors, some administrators and even some teachers unfortunately,) AP tests are imminent,  and lots of students have decided that the school year really ended after the Winter holidays.  It always felt like the end (of the school year,) was just around the corner and the excitement of learning about the living world was quickly fading away.  STOP!  CHANGE YOUR ATTITUDE!!  Either stay excited about the emerging life around you or get excited.  We have been telling our students all about how wonderful the biological world really is—-well, here it comes!  (At least in the northern part of the country.)  This is the pay-off for establishing all that understanding of how the natural world operates.  For discussing all the cycles and interactions and systems.  Get your students’ heads wrapped around the intricacies of life by watching it hatch, emerge, blossom, grow, sing, court, build, expand and multiply.  Plant some seeds, set up some nest boxes, record some songs (bird, frog, insect……,) photograph (buds, birds, bugs,  and babies,) count (eggs, salamanders, butterflies,  and fish,) and observe.  This is the time of the year when biology is exploding.  Open your windows if you can.  Take your classes into the biological world that is showing all those concepts you explained, all those systems you outlined, all those processes you explored.  The exponential acceleration of the biochemistry of the cell is happening in the house wren’s nesting, and singing and mating and hatching and feeding and rearing and teaching and fledging.  The year isn’t winding down, it is being reborn.  This is the payoff time for all your hard work explaining how biology works. Stop for a second, take a deep breath.  Reap the rewards of being the teacher that opened the living world to yet another group of youngsters.  Biology is the study of life, so go ahead and study it!

I dutifully waited my turn to pounce speak as the physics rep discussed the need for at least Algebra II skills and the chemistry teacher calling for at least Algebra I skills as prerequisites for their course–lamenting that even with these standard requirements, the students seem to have much difficulty “keeping track of units”, with proportional thinking, and with novel problem solving.  Generally, the argument presented was that physics and chemistry were math intensive–much like one long story problem.  I’ve taught all three courses and I didn’t really have any argument with most of their claims but it stuck in my craw as repeatedly the math, physics, and chem panel members kept referring to biology as the science that could be taught without a math emphasis—it still sticks in my craw. (I know, I know…a biologist shouldn’t really be implying that he has a crop–it’s just one of those homey, Kansas euphemisms.)

I went on to propose ideas for math applications across the broad scope of biology topics–Exponential functions/ equations, modeling, algebra in Hardy-Weinberg work, Fibonacci numbers, geometry, statistics and probability.  Not really demonstrating good political skills I went on in an accusatory fashion—”Why is it that the first exposure my students have to statistics and probability happens in my biology class?”  (Remember this was the 80′s.)  Obviously, the idea of math informing beginning biology instruction did not begin with me but you would have thought the audience had been suckered punched.  They were nodding their heads in agreement and about to start a constructive dialog when one of the old guard recovered quickly enough to dismiss my claims as being too unrealistic–I was jousting at windmills.  (This was also before Physics First or biotech investigations.)  Momentum lost for that round I learned my lesson and have been more politic in my approach.  To that end the landscape has changed a great deal, today.   However, despite supportive National Math Standards, Physics First curriucla, more AP courses taught, and numerous university or secondary level NSF projects funded to integrate more math in biology, it still seems that most biology teachers avoid math at all costs.  What’s my evidence?–no real hard data, just anecdotal experiences while trying to promote math and computer applications in the biology community.  Teachers are not, necessarily to blame.  I wish I could show you the looks on my student’s faces when they find out I expect some math application in biology.

My plan is to present a few posts that explore very basic math applications in biology–perhaps it will start a converstation….

In the meantime, here’s a warm-up from NABT member and former editor for the American Biology Teacher, John Junck:

10 Equations That Changed Biology (And That Should Change Biology Education)
Remember, there are only 10 kinds of people in the world—those that understand binary numbers and those that don’t.
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