On Thursday as Montclairions were excitedly monitoring the actions of a black bear strolling through the streets of downtown
Montclair, I was gleefully peering into a microscope at a much smaller bear. Of course it was not a black bear if you haven't already figured that out. It was something much more exciting to this biophile--a water bear! Water bears have many names: Tardigrade (its phylum), space bear, pudgy wudgy and my personal favorite, moss piglet.
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A water bear through a microscope, 100x. Picture by Nicholas Figuracion. |
My AP Biology class had collected some water and muck from Toney's Brook and I had decided to see what kind of microorganisms were present before I set the students free with the microscopes. The very first view of the very first wet mount I prepared contained the tiny creature above. I had placed a cover slip over the sample and I saw the eight stubby legs pushing against the glass as it plodded along. (Tardigrade, after all, means slow stepper.) Now, this picture, as neat as it is, does not really do the water bear justice. To truly see this creature in all of its glory, you need to see it magnified thousands of time more.
Isn't it cute? I just love these little critters! Water bears live almost everywhere on Earth and have even been to
outer space. They fascinate scientists and nature-lovers alike because they are practically indestructible and can survive some of the harshest conditions known. Recently, scientists have sequenced the water bear's genome and the results were just as strange as the creature's appearance. Almost one-sixth of the tardigrade's
DNA comes from other organisms, mostly bacteria, through a process called
horizontal gene transfer. Scientists believe that these foreign genes contribute to the animal's ability to survive such harsh conditions.
So, are you wondering whether my students were excited as I was at seeing all of the organisms living in Toney's Brook? I can say that they were with a resounding yes. We spent the whole period straining our eyes as we peered into this small-scale world. The brook on our own campus is teeming with life that is invisible to the naked eye--a world unbeknownst to students as they cross the bridge to visit the perennial food trucks.
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AP Bio students observing the microorganisms of Toney's Brook |
Teachers have good days and bad days. Any day that students are engrossed and fascinated by the natural world is a good day. And so I must say that this past Thursday was a very, very good day.
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