As a kid growing up in central Kansas, one of my special places was a wash out downstream from a concrete bridge that held water only after a significant rain.   We called this pool the Tadpole Pond and I can guess that you have a good idea why.  After every spring and summer rain when there was water in the pool, several of us in the neighborhood would round up our seines, jars, nets, and coolers in preparation of the big event–catching tadpoles by the hundreds along with the occasional crawdad, treasured green sunfish, black bullhead or snake.  For me and my friends the Tadpole pond was our African Water Hole–we learned a lot of biology in the mud and muddy water.  Who would have thought that a concrete bridge could create such a special place.

I have a new but similar special place where I keep track of the Kansas Aquatic environment and it too seems at first to be an unlikely spot:

This is a low-water bridge for the lake outlet as it crosses one of the main trails in Johnson County’s Kill Creek Park.  Remarkably, unimpressive as a natural area isn’t it?  I started building my own personal memories here about 6 years ago when I would coax my son into playing hooky from his PhD studies and convince him to bring his new daughter, Emma out for nature hikes with Grandpa.  One mid-May day at this particular site, Scott heard an unusual call that he thought was a warbler of some type.  While Emma and I played  on the concrete bridge Scott tracked down the calling warbler which he knew all along was a Black-throated Blue–he just didn’t want to make a bad call.  For me this has always been the BTB crossing….

This spring I stopped by this crossing on three separate days about 2 weeks apart.  On a whim in April I stopped after a significant rain–not planning on stopping at the crossing but when I got there I realized that I had picked a good day.  As I sat down next to the outlet tubes I observed in the thin water good numbers of darters and minnows making their way upstream to spawn–just like the more famous salmon.  The orange-throated darters would congregate just below the concrete apron and heave themselves in a mad dash in the fast current.  Because the concrete was so level I was able to get good views of darters, creek chubs and stone rollers as they made there way upstream.

This may be a pimephlales minnow followed by a male orangethroated darter.

Male orange throated darter Etheostoma spectabile

Females

I had a great time for the next couple of hours taking pictures and observing this early spring migration.

Later, in May I went back, the water was down and very clear.  I could see several green sunfish displaying to each other  in the pool, a black bullhead and a number of minnows.  Not thinking I’d see much else I was about to leave when I suddenly became aware (notice I didn’t say I observed them) of several Northern Water Snakes.  Once I was aware, I was astounded at the number of smallish water snakes that kept swimming upstream to this pool.  I never saw more than 6 at any one time but over the hour I was there, I estimate that I saw and average of a new snake every 1.5 to 2 minutes.  Most swam up the stream, to the pool and then tried to swim the concrete culvert–unsuccessfully.

This one decided not to swim…

I have no idea what the snakes were up to but it was another great day.  Actually, I do have an unproven hypothesis–I think the smaller snakes move upstream on these intermittent streams to access the new food resources that will be available  in the developing habitat and to exploit the pools as they dry up.

I returned two weeks later after another rain.  This time the water was cloudy and again I thought I really wouldn’t see anything but I was wrong.  While trying to get a picture of a young 5-lined skink on the same rock as the snake in the picture above, I happened to look down in the boiling muddy water in a small eddy just as a large common snapper (ever hear of a small one? lifted its head out of the water with an open gape just inches from my elbow–again I was too slow with the camera.   Each time I’ve visited the BTB crossing this spring, I’ve had an eventful day and like the darters I plan to return next spring for more of the show.

BW

Order Double Life of RNA from HHMI- It has the NOVA video and it is free. Click to order is on the left.

Or you can stream the video from http://www.pbs.org/wgbh/nova/sciencenow/3210/02.html

Now that you have a somewhat better idea of the RNAi mechanism go to the web site for Dolan DNA Learning center at Cold Spring Harbor, NY.
http://dnalc.org


From the main page locate the Silencing the Genome pages. This is the link from DNALC for C. elegans and RNAi . The live materials will be sent to you free. Just spend some time with the recipes before you order. Any questions be sure to contact me for help. Have fun and the students will have an opportunity to do real science. http://silencinggenomes.org/

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I’ll name the flower, later this week.

BW

BW

The Dolan DNA Learning Center (DNALC) is a pioneer in modern biology
education. Since it’s founding in 1988, more than 8,000 teaching faculty have
received intensive training at DNALC-sponsored workshops conducted in 42
states and several foreign countries. For 2008, we are offering a series of
exciting opportunities covering cancer, neuroscience, RNA interference,
molecular biology, bioinformatics and genomics. For applications and
additional information, please visit our Educator Training website at:

http://www.dnalc.org/ddnalc/teacher_training/

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]]> http://www.kabt.org/2008/05/22/free-update-workshops-from-coldspring-harbor/feed/ http://www.kabt.org/2008/05/13/delayed-season/ http://www.kabt.org/2008/05/13/delayed-season/#comments Wed, 14 May 2008 01:17:54 +0000 Brad Williamson http://www.kabt.org/2008/05/13/delayed-season/

In the first week of May of 2003 I took these pictures of Yellow-Lady’s Slipper Orchids.

They were past their prime by May 13th.  Today, I checked on the same orchids–they have not even budded, yet.  The leaves are still unfurling.  It’s truly a late spring for eastern KS.

BW

]]> http://www.kabt.org/2008/05/13/delayed-season/feed/ http://www.kabt.org/2008/05/13/the-wonderful-world-of-dung/ http://www.kabt.org/2008/05/13/the-wonderful-world-of-dung/#comments Wed, 14 May 2008 00:28:01 +0000 Brad Williamson http://www.kabt.org/2008/05/13/the-wonderful-world-of-dung/ For several years I kept a copy of a BBC production that was shown in the early 90’s on the Discovery channel: “The Wonderful World of Dung”. It’s the only video that I would not loan to others in the department–keeping it as a special treat for my students as we wrapped up the year. It’s a fun video that explores the importance of dung in ecosystems, in animal behavior and as an energy source–lot’s of connections. For the past several years I have scoured the internet looking for a legal source so that others could purchase legal copies for presenting to their students. No luck until a request was made to the AP Biology listserv. It seems that one of the AP f0lks has connection in Discovery and made a request to access the show again. If enough folks email discovery with a request, Discovery will either re-show the video or will market it in their store. Here’s the post with instructions:

Hi… so here’s the deal… if you want Discovery Channel to show the video on United Streaming or maybe re-release the video… you’ll need to email them with a request, please send a message to the customer support at Discovery Education at education_info@discovery.com.

Hopefully the deluge of requests will spark a response. Thank you to the 30 teachers who emailed me directly.

Robin Groch

]]> http://www.kabt.org/2008/05/13/the-wonderful-world-of-dung/feed/ http://www.kabt.org/2008/05/08/hardy-weinberg-spreadsheet-model/ http://www.kabt.org/2008/05/08/hardy-weinberg-spreadsheet-model/#comments Thu, 08 May 2008 16:51:36 +0000 Brad Williamson http://www.kabt.org/2008/05/08/hardy-weinberg-spreadsheet-model/ As part of the KABT thread at the recent KATS KAMP, I argued that we should be asking our students to use spreadsheets to model the concepts of population genetics–in particular Hardy-Weinberg equilibria. I tried to make the case that most of the efforts to model H-W equilibrium in classroom activities such as the AP Biology H-W lab, the M & M’s labs or with beans suffer from too small of sample size (population) or are tedious for the students to explore. On the other hand, working up your own models or having students create their own can be a challenge. The benefits to learning are worth the challenge. In this post, I’ll present the essential parts of an EXCEL spreadsheet that can be used to explore some of the first principles of the effects of population size on drift. This is not presented as the definitive spreadsheet model but rather a rather simplistic model accessible and modifiable by your students. BTW, it takes longer to read this post than it takes to make this relatively simple spreadsheet. I suggest that you bring up EXCEL or some other spreadsheet in a different window and try to create this worksheet as you follow these instructions. Once you’ve mastered this and can creat or modify it at will, then try it out with your students–they can handle this level of difficulty. And when do, they will have an effective tool to explore the basic principles of H-W equilibrium–one that they created.

Here’s what we are shooting for; the basic spreadsheet model for a 2 allele model:

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]]> http://www.kabt.org/2008/05/08/hardy-weinberg-spreadsheet-model/feed/ http://www.kabt.org/2008/05/06/carl-zimmers-new-book/ http://www.kabt.org/2008/05/06/carl-zimmers-new-book/#comments Tue, 06 May 2008 23:09:06 +0000 Steve Case http://www.kabt.org/2008/05/06/carl-zimmers-new-book/ A Science Writer worth reading - Case

Note from Carl Zimmer;

Hello–
I just wanted to let everyone know that at long last my sixth book publishes today. It’s called Microcosm: E. coli and the New Science of Life. You’ll recognize it at your local bookstore by the eerie glowing Petri dish on the cover. (And if you prefer Amazon, here’s the link: http://tinyurl.com/56m3cw )
Microcosm is about what it means to be alive. Are there rules that all living things must obey? Is death inevitable? If we rewound the tape of life and let evolution run a second time, would it end up like the original? To explore these questions, I’ve written an (un)natural history of E. coli. Scientists have been earning Nobel Prizes for decades now by poking and prodding this microbe, and their work is coalescing into an extraordinary portrait of a living thing. And today, with engineered E. coli spewing out everything from insulin to jet fuel, the microbe is redefining the boundaries of life itself.
Publisher’s Weekly praises MIcrocosm for its “elegant, even poetic prose,” calling it “essential reading.”
You can find an excerpt at my web site: http://carlzimmer.com/books/microcosm/excerpt.html
Also, if you live around Boston, Chicago, LA, Madison CT, New York, Portland OR, Seattle, or San Francisco, I hope you can come to one of my Microcosm talks. The details of my book tour are here: http://carlzimmer.com/talks.html
Thanks for putting up with a mass mailing. I hope you enjoy the book. (And please pass on the word to anyone who might be interested in it.)
Best wishes,
Carl
Carl Zimmer
email: carl@carlzimmer.com
web: http://www.carlzimmer.com

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