early aboriginal snowshoe design

 

 

Learning Objectives:

 

 

   Western Science perspective 

-  includes:

 

 

ü     Identifying weight and area as important factors for staying on top of the snow;

 

ü     understanding the concepts of surface area and pressure (weight per unit area);

 

ü     calculating pressure using scientific units appropriate to the students level (g/cm2 or Pascals).

 

 

 

   Aboriginal perspective –

Aboriginal people developed technologies related to winter that allowed them to use snow to their advantage.

Learning Outcomes:

 

 

Students will:

 

 

ü     Apply understanding of the concept of weight distribution of different snowshoe shapes over a specific area;

 

ü     Apply understanding of the chemical composition, physical states and properties and the insulation value of snow;

 

ü     Understand and compare Aboriginal and western science terminology related to snow and snow conditions;

 

ü     Understand the concept of pressure;

 

ü     Gain an understanding of animal ecological adaptation to snow;

 

ü     Increase measuring and estimating skills.

 

 

  LESSON OVERVIEW

 

 

 

 

What is snow

 

¨     Students can use a hand lens to look at snow flakes and crystals and draw their observations. To collect snow flakes, catch snow falling on pieces of COLD black construction paper that was cooled in a freezer.

 

¨   Collect and define the different words used to describe the types of snow and snow conditions in their own language. Use SchoolNet to explore how these differ from group to groups.

 

¨     Snow has many layers that can be examined and measured.

 

 

 

 

Activity

Collect different types of snow to measure the volume of water. Which type of snow (slushy, hard-packed, etc.) produces the greatest volume of water? What does that tell you about the snow?

 

How does snow insulate?

 

Snow traps air and air is an excellent insulator.  Any material that traps air is a good insulator. Caribou and polar bears have hollow hair. In fact, a polar bear is so well-insulated that it gives off almost no body heat and the bear's blubber layer can be 4.5 inches thick!  Infrared film is used to measure heat.  Polar bears do not show up in infrared pictures.  There is virtually no heat loss!

 

 

Activity

Testing the insulation quality of various materials!!

YOU WILL NEED: 

1.    Styrofoam, deer or moose hide, cotton, wool, newspaper, wax paper, aluminium foil, plastic bubble wrap, etc.

2.    fill plastic, tin or glass containers (all the same size) with snow or ice cubes – then wrap one of the insulation materials (from 1) around each container and secure with elastic bands or masking tape.  Remember to leave one container unwrapped for a comparison.

3.    have the class predict which insulation material will be best, which not so good, etc.

4.    measure water volume in each container after some pre-designated time period. The one with the least amount of water was wrapped in the best insulation.


ECOLOGICAL ADAPTATION TO SNOW AND COLD

Many animals have adapted to living in areas where snow and cold are around for many months of the year.  Snow provides a protective environment for many animals. Bears, chipmunks and skunks sleep through the winter. Weasels, voles and mice are active within the snow layer. Rabbits, grouse and Pine marten seek temporary shelter in snow.

 

Adaptations in anatomy and physiology help other species to survive and thrive in deep snow and cold weather:

ü     Lynx have very big feet, a luxurious fur coat and are relatively light weight. They are able to walk on snow in search of their main prey, the snowshoe hare.  The latter also have large feet and a white winter coat that helps them blend into the wintry woods.

ü     Moose have long legs and great strength.  They move through snow quite easily.

ü     Wolves have a warm fur coat and an ability to go long periods of time between meals.  They have thick hair, and skin muscles that raise hairs in the cold to provide greater insulation by trapping a layer of air next to the warm skin.

 

Other adaptations:

ü     Hollow hair, fat storage beneath the skin, fur, feathers and oils;

ü     Blood flow to the skin can be altered to reduce flow from the body core to the body surface, reducing the rate of heat loss;

ü     Torpor and hibernation, where the animal is in a state of reduced activity in which body temperature and metabolic rate decrease and heart and respiratory systems slow down;

ü     Large feet that provide a bigger base area for walking on snow;

ü     Snow shelter construction for getting away from cold and snow (polar bears, ruffed grouse).

 

 

 

Winter is a good time to learn about animal movements and habits.  The tracks they leave behind provide clues to their size, age, condition and activity.  Wolves often travel in groups.  They are a family unit and hunt large animals like moose.  Wolves generally travel in tandem through deep snow, with one wolf leading and others following. The last wolf in the line has the easiest as a trail has been well packed by the ones ahead.

 

 

  ABORIGINAL SNOW TECHNOLOGY

 

Some Aboriginal People live in cold climates where survival depends on reducing heat loss.  Humans use clothing for insulation.  Animals supply almost all the materials and food required to survive in cold climates. Snow is used to advantage for insulation and transportation.

 

Aboriginal snow knowledgesee Appendix 1 for Aboriginal snow terminology.

 

Getting around on snow   -   accomplished by spreading out the load by providing a larger base area.  Some examples are: snowshoes, skis on dog sleds and snow machines.  

 

 

  Snowshoes

 

HOW DO SNOWSHOES WORK?

Snowshoes spread out a load by providing a larger base area.

 

1.    The size of the area touching the snow is larger than, say, a pair of running shoes.

2.    A person’s weight is spread out over a larger area

 

Comparison exercise on weight distribution:

 

How many times lighter is a person walking on snow in snowshoes compared to a person wearing running shoes?

 

YOU NEED: A SNOWSHOE and a RUNNING SHOE

 

1.    Provide students with math formulas for areas of circles, rectangles and triangles.

2.    Measure (ESTIMATE) the area on the underside of a snowshoe by measuring the length and width and calculate the area, subtracting the parts that have been removed from the original shape used in the calculation.

3.    Measure (ESTIMATE) the area on the underside of a running shoe.

 

SOLVE FOR:   “How many times lighter?”

Answer: = the answer to #2 divided by the answer to #3.

 

DISCUSSION

 

 

The student’s weight is the same when wearing running shoes or snowshoes.  From the point of view of the snow, the pressure (= the push on the snow) is “x” times lighter when wearing snowshoes, because the weight is spread out over a greater area.

 

 

Ø    The GREATER the person’s weight the GREATER the “push” on the snow

Ø    The GREATER the area in contact with the snow, the LESS the “push” on the snow.

 

Pressure (=push)   = weight of object      Units = g/cm2

                                              area touching    

 

EXAMPLE:  Compare the pressure of a 50 kg. Student (=50,000 g) standing on one snowshoe and one running shoe:

          Underside surface area of snowshoe =             4,000 cm2

          Underside surface area of running shoe =            200 cm2  

           

PRESSURE with snowshoe           = 50,000 g          = 12.5 g/cm2

                                                              4,000  cm2

 

PRESSURE with running shoe      = 50,000 g          = 250 g/cm2

                                                              4,000  cm2

 

**PRESSURE is much less when wearing snowshoes compared to running shoes!

 

 

Activity!

 

Improvised Survival Snowshoes

See Appendix 2.

 

 

Students will use natural materials (spruce boughs, willow, etc.) and collected materials (recycled cardboard, plastic or other tubing, etc.) to make survival snowshoes.  They will summarize in journals and make a presentation to interested family members regarding what they learned about snowshoes.

 

Materials: cardboard, tubing, boughs, willow wands, traditional snowshoes, journals

 

Procedure

1.    Students collect natural and recycled material useful for making survival snowshoes.

2.    Construct a pair of snowshoes from the materials.

3.    Test out the snowshoes by holding races with the improvised snowshoes.

4.    Compare by having some students use traditionally made snowshoes.

 


RESEARCH PROJECTS

 

 

1.    Examine different ways of traveling on snow (snowshoes, sleds, toboggans, skis, snowmobiles) and how these work in relation to the different properties of snow.

What are the different styles of snowshoes?

What materials are used for sled runners and skis?

How are sled runners and skis treated to reduce friction?

Conduct experiments to illustrate these properties.

 

2.    Discuss the hazards of travel on snow (avalanches, crevasse, slush, snow insulating weak ice, slope and perspective, snow blindness).

 

3.    NEWTON AND PASCALS: Engineers and scientists calculate pressure in Pascals (Pa). The units are Newtons/ m2  (N/ m2) rather than g/cm2.

Who are Newton and Pascal? What is their contribution to our understanding of the physical world?

 

4.    Measure various shapes and sizes of snowshoes and estimate the weight of wearer. Refer to websites under Resources.

 

5.    Estimate animal paw size and weight and assess effectiveness for walking on top of snow. Peterson Field Guides on Mammals (for weight) and Animal Tracks (for paw size) are good sources of required data.

 

6.    Research how you could stay warm if you were stranded outside in a snowstorm?  What materials would you look for?  How would you construct a shelter?

 

7.    How would you construct snowshoes from materials available in the forest?

 

 

Resources and references

 

The following sources contributed useful information to lesson plan development.

 

SNOWSHOES

http://capes.usask.ca/ccstu/units/snowshoes.html

 

http://www.arctic-can.nt.ca/achodene/pages/footwear.htm

 

http://www.carlheilman.com/snowshoe10.html

 

http://www.ankn.uaf.edu/units/snowshoe.html

 

The Indians of Canada. Diamond Jenness.1977. University of Toronto Press, Toronto.

 

The snowshoe Book (3rd Ed.) The Stephen Greene Press. Brattleboro, VT. (ISBN 0-8289-0432-4).

 

ECOLOGY

http://www.polarbearsalive.org/

 

Mammals, Peterson Field Guides. 1976. W.H. Burt & R.P. Grossenheider (3rd Edition). Houghton Mifflin Company. Boston, MA.

 

Animal Tracks, Peterson Field Guides. 1974. Olaus J. Murie (2nd Ed.). Houghton Mifflin Company. Boston, MA.

 

 

Evaluation

 

 

Topics under RESEARCH PROJECTS, OR

 

Choose an Arctic People and describe how the society has changed from their traditional way of life as a result of snow machines, rifles, power boats, airplanes, oil drilling and mining operations.

Student or groups:

1.    describe the benefits of the new technology compared to the traditional way

2.    describe the dangers of change on fragile ecosystems

3.    discuss the measurements and possible effects of climate change on Arctic People and their traditional ways.

 

 

 

 

 

 

Critical Thinking

 

1.          Wheels vs. sled runners:  Has our technological “advances” in transportation provided us with more, less or the same abilities to live with snow?? 

Think about snow storms – which vehicles do we prefer to drive after a blizzard? Cars or snow machines?

 

2.          Can people and animals living in snow and cold climates adapt to global warming? 


TRADITIONAL KNOWLEDGE HOLDERS

 

Involvement in project

 

Students will gain a respect and understanding of their natural environment through the knowledge and skills demonstrated by community elders and “people who know”.

 

·        Traditional Knowledge Holders should be invited to actively participate throughout the project to provide information encompassing traditional values and beliefs.

 

·        Teachers should meet with the Knowledge Holder prior to starting the project to ensure that desired lesson outcomes are met.

 

·        Field Trips:

ü     Knowledge Holders accompany students on field trips where they will use snowshoes. Students and community Knowledge Holders will think and discuss and recognize different types of snow and terrain: walking on lakes, through lakeshore willows and trees, along animal trails and well-packed snow.

ü     Identify the trees, wood and animal parts that are used in snowshoe construction.

 

·         In class Community Knowledge Holders could demonstrate and teach students their expertise in making and using snowshoes (locating, collecting and preparing materials and methods of construction).


Appendix 1.

 

INUIT SNOW VOCABULARY

 

 

(a partial list of the several names for “snow” used by the Kobuk Valley Inuit, Pruitt, 1978)

 

Api (ah pee)                                - snow sitting on the ground

 

 

Pukak (poo kak)                        - the loose, recrystalized snow located next to the ground.

 

 

Upsik (up sick)                          - the hard wind-packed snow

 

 

Qamaniq (corn an nik)              - the areas of shallow snow at the base of trees

 

 

Siqoq (see cock)                        - drifting snow that will often reform as upsik

 

 

Siqoqtoaq (see cock tow ak)    - the icy layer on top of the snow (sun crust)

 

 

Mapsuk (map suck)                   - an overhanging drift of snow

 

 

Anjamana (un ya mun ya)         - the area where snow has been dug out by wind to form a drift