FEET AND FLOAT: Exploring an animal adaptation for life in the snow
Students learn about some animal adaptations for life in the snow by comparing features of pairs of similar animals that live in different environments. They explore their local area, searching for and learning to identify animal tracks in snow using a field guide. Using life-size stencils of selected animals from Alaska and other areas, students calculate the foot-load or weight-load of different animals and notice that animals inhabiting the snowiest environments tend to have lower foot-load values than those in less snowy environments. They experiment with the relationship between body weight, surface area, and depth of sinkage in snow by measuring how deep they sink in snow with and without snowshoes.
This set of activities includes many options; teachers can choose to do some or all of the activities according to students’ ages and interests and time available.
These activities complement “Feet, Float, and Physics: Exploring an animal adaptation to life in the snow,” an interactive online learning module for 6th grade and up available on the Our Winter World project website at: http://ourwinterworld.org/activity/. We encourage you to try it out with your students and share your feedback with us via the online comments form.
Snow and Living Things: Animals. 2020. Our Winter World website. http://ourwinterworld.org/snow-and-living-things/animals/
Blending In. http://ourwinterworld.org/snow-and-living-things/animals/blending-in/
Getting Around. http://ourwinterworld.org/snow-and-living-things/animals/getting-around/
Feet, Float, and Physics: Exploring an animal adaptation to life in the snow. 2021. Our Winter World website. http://ourwinterworld.org/activity/
How have plants and animals adapted in your area? UA REACH Curriculum, Unit 13: Your Environment, Lesson 13 – Grade 6. 2015. University of Alaska K-12 Outreach. https://www.alaska.edu/k12reach/grade6year3.php
Folding Animal Track Pocket Card to download and print. Alaska Department of Fish and Game. https://www.adfg.alaska.gov/static/education/educators/pdfs/track_pocket_card.pdf
Why are my feet so big? Lesson plan. 2020. Alaska Department of Fish and Game. (Contact Fairbanks Office for information)
Materials necessary for activity.
Our Winter World: Animal adaptations to living in the North (PowerPoint presentation file on flash drive in materials kit)
● Animal Tracks of Alaska field guides (4)
● measuring tape (dual metric/imperial scale) (2)
● clear 1 inch x 1 inch gridded acrylic boards (4)
● dry erase markers (1 set, assorted)
● dry erase cleaning fluid (1 bottle)
● Set of animal track stencils (assorted)
● graph paper (choice of 1 inch x 1 inch grid or 1 cm x 1 cm grid)
● snowshoes (1 pair)
1. Introduce animal adaptations to northern environments
Read instructions on first slide of PowerPoint presentation, then display PowerPoint presentation, moving animal photos to the appropriate columns according to student input. (If easier, you may also print the presentation, cut out the animal pictures, and ask students to sort them manually according to each characteristic, revealing the animals’ geographic range after each sorting task.)
Tell the students that the rest of the activities in this lesson will focus on animal feet. What did they notice about the size of more northerly animals’ feet in comparison to similar animals from more southern/less snowy locations? Animals inhabiting very snowy environment tend to have larger feet compared to their body size and weight as compared with animals inhabiting less snowy environments. Ask for suggestions as to how this might help animals succeed in the north, and in the snow in particular? (Larger feet relative to body weight results in lower foot-load or weight-load, which means that the animal exerts less pressure on the surface of the snow than would a heavier animal or one with smaller feet. This helps these animals “float” on top of the snow better, making it easier and less energy-intensive for them to travel from place to place in winter.)
2. Outdoor exploration: Identifying and measuring animal tracks
Ask students to share stories about what animals they have seen lately and about different types of animal tracks they see in the area and can identify. Guide them in browsing though the animal track field guides, coaching them to interpret range maps, gait patterns, dimensions and labels, and any differences between front and hind feet or juvenile and adult tracks.
Optional: Allow students to take photographs one or two pages of the field guide with their phones so that they can refer to the pictures in the field. OR, if time allows, make photocopies of selected pages of the field guide for tracks that you are likely to find near your school and create half-sheet sized laminated track cards that can be taken out in the field.
Go outside to explore and find animal tracks, identifying what type of animal made the tracks when possible. Note how deep the animal tracks are in the snow, and estimate how recent the tracks are based on the most recent snowfall event.
Optional: Try tracing a good track or set of tracks using the clear acrylic gridded board. To do this, lay the board, grid side down, on top of the track. If the snow is very new and soft, the board might sink in and ruin the track. If it stays in place and you can see the track through the clear board, however, use a dry erase marker to trace the outline of the track on the plain acrylic (plexiglass) side of the board. Take the board inside and set it down so that the plastic grid is face up. Count the number of 1 inch squares that fall within the track outline that you drew. One method that is helpful for finding the total area of the track is to count every square that is at least half inside the outline of the track. Don’t count the squares that are less than half inside the track outline. The total number of squares that you count will add up to the area of the track in square inches.