y Names A Cat of Man ty ll this big kit Scientists ca g in d lor. Depen puma conco ay m u live, you on where yo : know it as a on li • mountain • cougar • puma unt • catamor • panthe r what you But no matte names refer se call it, all the e of cat. p ty e m a to the s 1 DynaMath • To order, call 1-800-SCHOLASTIC or visit www.scholastic.com/buy-dynamath JEREMY WOODHOUSE/PHOTODISC/GETTY IMAGES ANALYZING DATA TRENDS Secrets of the Hunt Scientists uncover how the clever cougar tackles its jumbo prey B iologist Terrie Williams has studied big cats for 31 years. And yet, she had never found an answer to a basic question about these animals: How does a single 100-pound cat take down prey up to six times its size? Using new technology, Williams and a team of researchers from the University of California, Santa Cruz, recently set out to find the answer for cougars, a type of big cat. It’s the key to understanding how the animals survive. Big Comeback Williams and her team knew that observing cougars hunting in the wild wasn’t likely. People rarely see these shy, secretive hunters. And although thousands of cougars now roam the mountains of the western United States, they had nearly become extinct from the U.S. a century ago. Their major comeback is the result of laws that protect the cats. In recent decades, the increase in cougar numbers has allowed scientists to study the cats more closely. But Williams and her team needed a high-tech solution to unlock the secrets of the big cats’ hunting style. continued on page 3 ➜ 2 Smart Collar, Clever Cat This SMART collar gathers data on the cougar’s location, movement, and energy usage. Researchers sedate a cougar so they can weigh and collar it. Then they release it back into the wild. fact, they tend to walk very slowly, which saves energy. The crafty cats also adjust their hunting strategies depending on the type of meal they’re pursuing. A cougar may stalk only briefly to snag a raccoon. It saves its most powerful pounces for prey like the mighty elk. “We found that they’re very efficient when they hunt for food,” Williams says. Protecting Their Home Scientists say that understanding a cougar’s hunting style is important for protecting the animals’ future. For example, destruction of the 3 DYNAMATH • APRIL 2015 trees and plants the big cats use for cover while hunting could threaten their survival. It would make hunting more difficult, and the cats could starve. Williams hopes further studies will uncover whether this sort of habitat loss has increased the energy demands on cougars and, if so, by how much. “Now the collars are available to people around the world to study all types of animals, from lions to wolves to polar bears,” says Williams. “This technology gives us a whole new level of understanding that can really help move conservation forward.” —Natalie Smith PAGE 3: BRUCE KELLMAN/THE NEWS TRIBUNE/AP PHOTO (RESEARCHERS AND COUGAR); COURTESY OF T.M.WILLIAMS/UC SANTA CRUZ (COUGAR COLLAR); PAGE 4: MATTHEW STAVER/LANDOV (COUGAR ON TREADMILL) The team developed a device called a SMART collar that can measure a cat’s movements, speed, and calories burned. But before they could use the collars on wild cougars, they needed to study captive cougars to understand how the collars would track a cat’s energy use during different activities. The researchers attached the SMART collars to three cougars in a wildlife park in Colorado. They monitored the animals performing a wide range of activities, from grooming to pouncing. Over eight months, they even trained the animals to run on a treadmill! After gathering data for each activity, the team was ready to put the collars on wild cats in the Santa Cruz Mountains. The researchers found that wild cougars do high-energy activities, like running, only for short periods of time. In Analyzing Data Trends Graphs and coordinate planes help us analyze trends, solve real-world problems, and make predictions. Williams and her team collected and graphed the data from their SMART collars. The graphs tell the story behind how cougars hunt. Let’s say Williams makes a graph of a female cougar’s movement patterns during a hunt. Use the information in the graph to answer the questions that follow. Female Cougar’s Speed During a 120-Minute Period SOURCE: INSPIRED BY THE RESEARCH OF WILLIAMS ET AL. SPEED (miles per hour) 50 40 30 20 10 0 0 20 40 60 80 100 120 TIME (minutes) 1 What is the cougar’s maximum speed? 2 During which time interval did the cougar remain stopped for about 10 minutes? 3 What does the graph tell you about this cougar’s movement patterns during a hunt? 4 Why is a line graph a good way of displaying this data? Let’s say a male cougar’s SMART collar gives the following data over a 20-minute period. Use the data to sketch a line graph. Then answer the questions that follow. A Cougar’s Speed Over 20 Minutes Time (minutes) 0 5 10 15 20 Speed (mph) 2 3 1 0 0 5 After how many minutes did the cougar’s speed fall to 0 mph? 6 How long did the cougar remain stopped? 7 The team trained three captive cougars to walk and run on a treadmill as part of the study. Based on the data, what might the cougar have been doing during that time? Watch A Video scholastic.com /dynamath FOR SUBSCRIBERS ONLY 4 LESSON PLANS page 1 Analyzing Data Trends Secrets of the Hunt Content Standard Measurement and Data Mathematical Practices Standards 3. Construct viable arguments and critique the reasoning of others 4. Model with mathematics 5. Use appropriate tools strategically OBJECTIVE Students will use the data from the line graph to analyze and interpret data on cougars and their activity levels. Materials graph paper LESSON Engagement 1. Before reading the article, ask questions and facilitate discussion either as a whole group, in small groups, or with a partner: •Have any of you ever seen a big cat (such as a lion, tiger, or cougar) at the zoo or in the wild? •How fast do you think it can run? •Discuss how long you think a big cat can run at the speed you predicted. Concept Development 2. After reading the article, ask the following: •Discuss the type of graph the article uses to represent the data. •What does the data in the graph represent? •Discuss why this type of graph was chosen to represent the data. (As the discussion progresses, be sure to clarify and correct any misunderstandings the students may have.) 3. Project the graph at the top of the next column for all to see. (You can also project the color version on page 4 of the article.) Discuss as a class: Who can identify and circle the graph’s title? (Female Cougar’s Speed During a 120-Minute Period) •Who can identify and highlight the graph’s y-axis? What does it stand for? (speed) •Who can identify and underline the graph’s x-axis? What does it stand for? (time) •What unit is speed represented in? By what increments are these units increasing? (miles per hour; they’re increasing by 10-mph increments) •What unit is time represented in? By what increments are these units increasing? (minutes; they’re increasing by 20-minute increments) Application 4. Have students work on problems 1 through 4. Once they are finished, have them share their solutions and look for similarities or differences. 5. When students create their own graph for problems 5-7, remind them to be cautious with their units and x- and y-axis increments. The increments may differ from the graph in the first problem set. Students must decide on increments that may be more appropriate. Closure 6. Extend this activity by having students create their own line graph that represents something from their everyday lives. Concept Reinforcement Online www.scholastic.com/dynamath Click on the “Skills Sheet” button in your digital issue for the “Coordinate Grid Stories” skills sheet. Students will get more practice problem solving with a coordinate grid. (Also availableattached below.) DynaMath • To order, call 1-800-SCHOLASTIC or visit www.scholastic.com/buy-dynamath NAME _______________________________ Coordinate Grid Stories In “Secrets of the Hunt” (pages 1-4), you used graphs to understand how cougars hunt. Plotting data on a coordinate grid can help us see the meaning behind the numbers. For example, a runner tracks his pace (time per mile) during a half marathon, a 13-mile race. By studying the data, we can form an educated guess as to what the runner was experiencing during the race. Use the chart below to create your own graph and answer the questions. DISTANCE PACE DISTANCE PACE Mile 1 9 minutes/mile Mile 8 10.5 minutes/mile Mile 2 6 minutes/mile Mile 9 11 minutes/mile Mile 3 6 minutes/mile Mile 10 12 minutes/mile Mile 4 8 minutes/mile Mile 11 15 minutes/mile Mile 5 8.5 minutes/mile Mile 12 11.5 minutes/mile Mile 6 9 minutes/mile Mile 13 10.5 minutes/mile Mile 7 9 minutes/mile 1 Use the information in the chart to graph Jeremy’s speed during the half marathon. Don’t forget a graph title and to label the axes and their units. 2 During which two miles did Jeremy run the fastest? [Hint: The lower the number of minutes/ mile, the less time it took Jeremy to travel one mile.] DynaMath • To order, call 1-800-SCHOLASTIC or visit www.scholastic.com/buy-dynamath • Page 1 of 2 Scholastic Inc. grants teachers permission to reproduce this page. ©2015 by Scholastic Inc. All rights reserved. Jeremy’s Half-Marathon Pace 3 he race’s course included a large hill that runners had to climb toward the end of the course. T According to Jeremy’s pace, at what mile would it be reasonable to think that he encountered this hill? 5 During which four-mile interval did Jeremy’s running speed remain the same, give or take 1 minute per mile? How much did Jeremy’s pace change between mile 11 and mile 13? Why do you think that was? Scholastic Inc. grants teachers permission to reproduce this page. ©2015 by Scholastic Inc. All rights reserved. 4 DynaMath • To order, call 1-800-SCHOLASTIC or visit www.scholastic.com/buy-dynamath • Page 2 of 2
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