Polar bears are built to withstand some of the coldest temperatures on the planet. Their brown and black bear cousins avoid the winter cold by digging dens and sleeping. But, except for pregnant females, polar bears spend the arctic winter outside where temperatures could be -40° F (which equals-40 °C) and windy. That’s too cold for humans. You could go outside, but only for only a few minutes with every part of your body completely covered. And if you didn’t wear goggles, your eyelashes would freeze and break off if you touched them. Polar bears are warm-blooded like us with a body temperature of about 98°F/37°C. But they are invisible to night-vision goggles that pick up the infrared rays that warm-blooded creatures, including humans, give off. Why? Nature has given polar bears enough insulation to prevent body heat from escaping. They are toasty warm and comfortable in the frigid arctic. Their heat insulation is in several layers. Under their skin, there is a 4-inch (21.5 cm) layer of fat. Next to the skin is a dense layer of woolly fur that also keeps heat in. The fur you see is a thick layer of long, colorless guard hairs that shed water quickly after a swim. They are stiff and transparent and hollow. In the arctic sunlight, the hairs act like mirrors and reflect white light, which acts as camouflage against the snow so the bears are not seen by their prey. Polar bear skin is actually black, so that it can absorb the invisible warm infrared rays of the sun and the bear’s own body heat, both of which are reflected back by the guard hairs. Most warm-blooded animals raise their body temperatures through exercise. Polar bears hunt seals, which they don’t often chase. They prefer to sit at the edge of an ice floe and wait for dinner to arrive. At best, they’ll lumber after a seal at four and a half miles (7.25 km) an hour, raising their body heat to 100°F (38°C). When that happens, they go for a swim to cool off. Cold won’t kill off the polar bears, but global warming can. As polar ice disappears, so does the hunting ground for seals. Not so cool!  The polar bear is the largest land carnivore. Its long non-retractable claws help it get a grip on the icy surface it prowls for prey. Wikimedia Commons  Close up, the polar bear guard hairs are transparent. This allows the infra-red light (heat) from the sun to pass through them to be absorbed by the black skin under the hairs. The hairs also act like mirrors , reflecting back to the skin any infra-red radiation escaping from the bears body so it can be reabsorbed. Thus, the insulation is just about perfect with no infra-red radiation escaping. The hairs are also coated with oil so they drain quickly after a swim.  The polar bears’ white appearance serves as ideal camouflage in a snow-covered environment. Art by Barbara Lavelle from This Place is Cold by Vicki Cobb.  Vicki Cobb's This Place Is Cold shows how the latitude of Alaska affects the lives of the plants, animals and people who live there. It is gloriously illustrated by Barbara Lavallee, a long-time Alaskan resident and artist. Vicki is a member of Authors on Call—she can visit your classroom with interactive videoconferencing: Read more about her here. MLA 8 Citation Cobb, Vicki. "The Way Polar Bears Keep Warm Is Cool." Nonfiction Minute, iNK Think Tank, 29 Nov. 2017, www.nonfictionminute.org/The-Way-Polar-Bears-Keep-Warm-Is-Cool. 
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Question: If your favorite snack was just out of reach, what would you do?
That’s what Preston Foerder, who studies animal behavior, asked Kandula, a male Asian elephant at the Smithsonian National Zoological Park in Washington, D.C. Scientists have always thought that using a tool to solve a problem was a sign of higher intelligence. They also thought that only humans were tool users. But then Jane Goodall discovered chimps using sticks to fish termites out of a hole, and ravens were observed making hooks to nab a treat. People who’ve worked with elephants have long known that they are highly intelligent, but no one ever tested an elephant’s ability to use a tool to solve a problem. To set up the experiment, Preston skewered Kandula’s favorite fruits on a branch and suspended it well out of trunk reach. Then he scattered potential tools such as long bamboo sticks and a heavy-duty plastic cube around the yard. At first Kandula just stared at the fruit longingly. Occasionally he picked up a stick, but only played with it. On the seventh trial, Kandula got an idea. He rolled the cube several yards so it was beneath the fruit. He placed his two front feet on the cube, stretched his trunk as high as he could, and plucked the fruit off the branch. The next day, as soon as Preston suspended the fruit, Kandula was already shoving his cube into place. He seemed to enjoy his new tool. He used it to peek over walls, to check out birds in a nearby tree, and to eat blossoms off another tree that grew outside his yard. Later, Kandula showed off by using a tractor tire and then a large ball as a stool. He even figured out that if he stacked one small block on top of another he might be able to reach higher fruit. Although he came up short (he needed to stack 3 blocks), he still showed that his brain was working out the problem. So, congratulations! If you said you’d use a stool to reach your favorite snack, then you are as smart as an elephant. 
Through carefully planned and executed games or problems that they give to elephants to test their intelligence, an organization called Think Elephants International has started to explore how animals think. For more information, click here.
Peggy Thomas is co-author of Anatomy of Nonfiction, the only writer’s guide to crafting true stories for children. She is currently working on a book about elephant intelligence. To learn more, visit her website.
Peggy Thomas is a member of iNK's Authors on Call and is available for classroom programs through FieldTripZoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.
MLA 8 Citation
Thomas, Peggy. “Are You as Smart as an Elephant?.” Nonfiction Minute, iNK Think Tank, 17 Nov. 2017, www.nonfictionminute.org/are-you-as-smart-as-an-elephant? 
Earth’s temperatures are getting warmer. In fact, sixteen of the seventeen hottest years on record have occurred since the year 2000. These warmer temperatures are driving larger, long-term changes in our planet’s weather and climate. Scientists refer to these changes as “climate change.” In a few places, climate change might be welcome, but around the world, warmer temperatures and other changes are leading to a host of problems from rising sea levels to more extreme weather events and the spread of harmful human diseases. Professor Scott Mills, from the University of Montana, wanted to see how climate change might be affecting one particular animal called the snowshoe hare. Snowshoe hares live in regions of North America that receive snow every winter. The hares, in fact, change their coat color from brown to white and back again every year. This helps camouflage them against their background—and hides them from the eyes of lynx, owls, and other hungry predators. Here’s the thing: snowshoe hares can’t choose when they molt, or change their coat color. Molt timing is controlled by their genes, which are part of the DNA inside their bodies. If a hare’s genes make it molt to white in October, but snow doesn’t fall until December, the hare will stick out like a light bulb against the brown earth. And that’s a problem. Why? Because almost everywhere on earth, the length of time with snow on the ground is growing shorter and shorter. To find out if shorter winters might harm hare populations, Scott and his team spent three years tagging and following hares. They measured how many were born, how many died, and what they died from. They also recorded whether the hares were matched or mismatched against their backgrounds. They discovered that predators killed mismatched hares significantly more often than hares whose coats match their backgrounds. Scott and his team also calculated that over the next one hundred years, this greater mortality, or death rate, could lead to the decline or disappearance of many snowshoe hare populations. The good news? Different hares molt at different times. This may help some hare populations adapt to shorter winters and longer periods without snow. Hares are not the only animals affected by shorter winters. More than twenty species of animals including lemmings, weasels, hamsters, and Arctic foxes change their coat colors every year. Scott’s research helps us predict what might happen to these animals—and decide what we can do to protect them.  Scott’s discoveries about Montana snowshoe hares, together with experts’ predictions about our future climate, indicate that hares will be mismatched between 5-½ and 10 weeks by the end of this century.  Before tagging and putting a radio collar on a snowshoe hare, Professor Mills and his team must weigh and measure it.  This snowshoe hare has been tagged and fitted with a radio collar—and is now ready to help scientists learn more about snowshoe hare survival.  Even from a great distance, a mismatched hare stands out like a glowing light bulb. (Photo Courtesy of L. Scott Mills research laboratory)  Besides serving as popular prey for predators, snowshoe hares are irresistibly cute. This is a young hare, also called a leveret.  Sneed B. Collard III is the author of more than eighty award-winning books, many focusing on science and the natural world. His entertaining memoir Snakes, Alligators, and Broken Hearts—Journeys of a Biologist’s Son recounts his challenges and adventures growing up as the son of divorced biologist parents, and the experiences that would one day lay the foundation for his writing career. He is a dynamic speaker and offers school and conference programs that combine science, nature, and literacy. To learn more about him and his talks, visit his website, www.sneedbcollardiii.com. This book was reviewed by Vicki Cobb in the Huffington Post: "The Cheeseburger of the Forest". MLA 8 Citation Collard, Sneed B., III. "Hopping Ahead of Climate Change." Nonfiction Minute, iNK Think Tank, 15 Nov. 2017, www.nonfictionminute.org/hopping-ahead-of-climate-change. 
Are skunks aggressive, dangerous animals? Or are they peaceful animals that try to avoid trouble? Well, biologists who study skunks think of them this way: if life were a sport, skunks would be known for their strong defense and for playing fair. Skunk stinkiness comes from a chemical weapon called musk. Foxes, weasels, and some other mammals also produce musk, but skunk musk is especially strong and long-lasting. And only skunks use musk to defend themselves from attack. Picture a skunk ambling along in the night, looking for food. It digs in the soil to get tasty earthworms and beetle grubs. The black and white fur that comes with just being a skunk sends a warning. This color pattern is unusual among mammals. It signals: "Beware, don't mess with me!" Suppose a coyote or other predator ignores this first warning. It steps toward the skunk. When a skunk feels threatened, it faces the danger. It raises its tail and tries to look as big as possible. It stamps its feet and clicks its teeth together. It may growl or hiss. Oh, oh! Despite all of these warnings, the coyote growls and comes closer. Now the skunk gets really serious. It twists its body into a U-shape, so it can see the coyote and also aim its rear end toward it. The skunk's tail arches over its back, away from its rear—the final warning. This gives the skunk a clear shot, and also protects its own fur from the stinky musk. Skunks try to avoid smelling bad! From two grape-sized glands, a skunk can spray musk as a fine mist, or squirt a stream. It can squirt accurately for about 12 feet (3.7m), and hit an attacking animal right in the face. The musk stings the predator's eyes, and can blur its vision for a while. And it stinks! Animals hit with this musk learn to never bother a skunk again. A skunk's glands store enough musk to fire a half dozen shots but then need a week or so to produce more. This is seldom a problem, since a skunk sprays only when its life seems to be in danger. Some skunks can go for months or even years without spraying musk. That's fine with them. Skunks want to avoid trouble, and "play fair" with their many warnings.  A skunks’s stripes point to where the spray comes out. A 2011 study found that animal species that choose fight over flight when faced with a predator often have markings that draw attention to their best weapon. So while a badger has stripes on his face to highlight his sharp teeth, skunks’ stripes are perfectly positioned to highlight their ability to spray potential threats. By http://www.birdphotos.com via Wikimedia Commons  Skunks are so nice that some people want to keep them as pets. The striped skunk is the most social skunk and the one most commonly domesticated. The legality of keeping skunks as pets in the US varies by state, with it being illegal in a majority of them. By Matt MacGillivray via Wikimedia Commons  Larry Pringle has written many animal books, among them The Secret Life of the Red Fox. His The Secret Life of the Skunk will be published by Boyds Mills Press in 2019. It is about spring and summer in the lives of a mother striped skunk and her kits. ML 8 Citation Pringle, Laurence. "How Skunks Play Fair." Nonfiction Minute, iNK Think Tank, 8 Nov. 2017, www.nonfictionminute.org/how-skinks-play-fair.  
My knees shake as I stand behind Poonlarb, a towering female Asian elephant who rocks back and forth while the veterinarian explains the procedure. I pull on a rubber glove that goes up to my armpit, and grease my entire hand and arm with a lubricant. Taking an elephant’s temperature is one way the vet can assess the animal’s health, which is important at the Golden Triangle Asian Elephant Foundation (GTAEF) in Thailand where many of the elephants have been rescued from harsh lives hauling lumber, or begging on the busy streets of Bangkok. The GTAEF is one of many organizations struggling to protect abused, captive elephants, as well as educate people on the plight of the dwindling wild population. Loss of habitat and poaching for ivory has made the Asian elephant ten times more endangered than their big-eared African cousin. When the vet hands me the thermometer, I laugh. I was expecting something…well… elephant-sized. But the thermometer is no bigger than the one I use at home. Protecting the glass tip with my finger, I ask Poonlarb if she’s ready, and inch my hand into her rectum. “More,” the vet says, and I reach further pushing up on my tip-toes. Poonlarb’s muscles gently contract around my arm. If the mahout (elephant handler) wasn’t holding her tail, this nearly two ton female could easily knock me off my feet with one swish. I rub Poonlarb’s rump, and assure her it will be over soon, but four minutes is a long time when you have your hand up an elephant’s backside. I pull the thermometer out and hand it to the vet. “36.2 Celsius,” she says. “Normal.” That’s 97.2 degrees Fahrenheit. Poonlarb is one healthy elephant, and luckily for me, a patient patient.  Peggy Thomas learning a new skill to add to her resume.  Peggy Thomas not only knows something of the anatomy of an elephant, but she knows the internal structure of nonfiction. Peggy Thomas is a member of iNK's Authors on Call and is available for classroom programs through FieldTripZoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.  MLA 8 Citation Thomas, Peggy. “How to Take an Elephant’s Temperature.” Nonfiction Minute, iNK Think Tank, 23 Oct. 2017, www.nonfictionminute.org/the-nonfiction-minute/how-to-take-an-elephants-temperature. |
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For Vicki Cobb's BLOG (nonfiction book reviews, info on education, more), click here: Vicki's Blog *NEWSFLASH *
The NCSS-CBC Notable Social Studies Committee is pleased to inform you that 30 People Who Changed the World has been selected for Notable Social Studies Trade Books for Young People 2018, a cooperative project of the National Council for the Social Studies (NCSS) & the Children’s Book Council Categories
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