Shrew poo and worm goo are science too

Last week I had the pleasure of being a speaker at Buck Lodge Middle School’s Career Day. Several public schools in Maryland, where Buck Lodge is located, and other states organize important events like these to get students thinking about future opportunities. Do you remember what it was like to be in middle school? To the middle school me, a career seemed distant, vague and, frankly, too overwhelming to really think about. But the big question was always on my mind: What do I want to be? As I told the students at Buck Lodge, at the time, I knew I enjoyed writing and painting and found science fascinating, but that was the scope of my “career path.” I chose a high school and college known for their science programs—seemingly small decisions that actually said quite a bit about my true interests. But it wasn’t until a couple years into college that my advisor told me about a career in science writing; the more I learned about it, the more I knew it was the right fit. I was able to learn about the latest research and share it in creative ways. As I tried to express to the students, this is why I chose science: It can be fun, weird and important all at once, and it can show you a side to the world you never knew existed. So when I explained my career to the students at Buck Lodge, I wanted to show my excitement about the two main components of my job: science and writing. The science part was, naturally, what the students found most entertaining. At the beginning of each class, I asked the students how many of them liked “science, any kind of science.” Usually a sprinkling of hands rose. Then when I asked how many students liked animals or bugs, the hands shot up. “That is what I do,” I said, “I write about animals, bugs, plants, bacteria and how they all interact with each other and their environment. This science is called ecology.” The students inevitably wanted to know about the “coolest” or “weirdest” thing a (ecological) scientist has studied. I asked them if they had heard of the water bear. In one class, the students logically guessed a water bear is a bear that is particularly good at swimming. But the room erupted in “Ew!”s and “Gross!”s when I explained that the water bear is a microscopic animal living in mosses and wet environments all over the world—that they may have actually touched a water bear and not even known it. The students continued to comment on its translucent cuticle...

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Two surprising critters living in the tiny world of moist soil

The unseen world of soil microbiota is full of surprises: Take, for instance, tiny animals called water bears that thrive in almost any location on Earth (and even outer space) through suspended animation. And even a shape-shifting slime mold that cultivates bacteria in order to  harvest it in the future. These are only two of the organisms populating soil—yet there are hundreds of other microcritters on which plants and larger animals rely. Water Bears Water bears, which are named for the bear-like gait with which they walk, use claws at the end of eight pudgy legs to cling to leaves, moss and other debris. Stylets at the end of a tubular mouth pierce plant cells and small invertebrates (and even other water bears in some cases) while a pharynx sucks out the juices. Water bears—officially called tardigrades and also known as moss piglets—possess a compartmentalized brain and nervous system, intestine, eye sockets, anus and, in most cases, gonads.  Some species reproduce internally through intercourse while others rely on fertilizing eggs externally. Water bears are found in moist soil and in extreme environments as well. They also thrive in an ecosystem in Antarctica, in boiling hot springs and can even tolerate long periods (up to a decade) of dehydration. Whereas a majority of living organisms die if exposed to extreme dryness, called dessication, water bears have evolved a unique characteristic: “They can reversibly enter a state of suspended animation called cryptobiosis, in which their metabolism screeches to a halt and their water content plunges to a hundredth of normal,” as the blog The Artful Amoeba described. “This helps protect their DNA, and a sugar called trehalose helps protect their membranes.” In addition, water bears are the only animals to survive the radiation-intense, extremely dry vacuum of space—and later recover to breed again. Slime molds These are definitely not your garden variety slugs. Technically Dictyostelium discoideum, also called slime molds, are social amoeba commonly found in soil. And despite also being featured in science labs as a model organism, it was not until recently that researchers discovered these single-celled organisms were also avid farmers. When times get tough, such as when there is a shortage of bacteria for the slime molds to consume, the individual amoebas will join forces to form a slug and migrate to another location. Once it arrives at a suitable locale, the slug again changes shape—this time into a plant-like formation complete with a stalk and a spore. D. discoideum stays “planted” in this shape until food becomes available; then the stalk dies and the spore breaks free to form amoeba once again. D. discoideum research published...

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