By the end of this activity, students will:

1) understand how film and photographs are used in scientific inquiries.

2) estimate the size of an adult cheetah by research and measurement of a picture.

3) determine the approximate distance of the filmed chase.

4) determine the approximate speed of the cheetah in the film.

5) compare their fastest running speed to that of a cheetah.

Related National Standards

Science

1) Knows ways in which species interact and depend on one another in an ecosystem (e.g., producer/consumer, predator/prey, parasite/host, relationships that are mutually beneficial or competitive).

2) Knows that an object's motion can be described by tracing and measuring its position over time.

3)Knows that scientific inquiry includes evaluating results of scientific investigations, experiments, observations, theoretical and mathematical models, and explanations proposed by other scientists (e.g., reviewing experimental procedures, examining evidence, identifying faulty reasoning, identifying statements that go beyond the evidence, suggesting alternative explanations).

4) Knows that although the same scientific investigation may give slightly different results when it is carried out by different persons, or at different times or places, the general evidence collected from the investigation should be replicable by others.

1) copy of the program "The Living Edens: Etosha"

2) VCR capable of slow motion or frame-by-frame play

3) side view picture of a cheetah

4) ruler

5) calculator (if desired)

6) timing device

This activity will take 3 to four days to complete as written. It may be modified to take as little as one day if only the film and calculations are used. Day one: introduce the ideas and do the research. Day two: take measurements on the film and do the calculations. Day three: time the students and have them calculate their speed. An extra period will be needed to watch the video for the first time.

Background Information The cheetah, Acinonyx jubatus, is a large cat found in regions of Africa with remnant populations reported in Iran and Afghanistan. It closely resembles a leopard but has a longer body and longer legs. The average cheetah has a weight of 50-60 kg (110-130 pounds), a body length of about 140 cm (4.5 feet), a tail length of about 80 cm (2.6 feet) and stands about 80 cm (2.6 feet) at the shoulder. The cheetah is widely said to be the fastest animal on earth with speeds reported in a range from 45 to 68 miles per hour (7-109 km/hr). However, this burst of speed can only be maintained for a short amount of time, usually well under a minute, and is the high-end exception rather than the average pace. While dashing after prey, the cheetah has a bounding run where the rear legs push the cat forward to a full body extension. Once extended, the front feet are planted and the rear feet brought forward and planted next to the front feet so the cat can extend once again. Of course, this happens very quickly and in some chases the gait can change during the pursuit. Scientists often film and photograph events in nature and analyze and measure the results. Action sequences are often studied in slow motion. Probably the best examples of this method of analysis are films of tornadoes. In this film, a distant shot of a cheetah chasing its prey allows estimation of the speed of the animal and the distance it covers. The sequence is a clear shot 12 minutes into the film where the animal is running across an unvegetated flat. From the start of the filmed run, the cheetah bounds 53 times to where it turns to make the final attack. Students will time this sequence at about 18 seconds. Assuming the cheetah is of average size, this will allow calculation of a run distance of approximately 514 feet (157 m) at a rate of 28.5 feet (8.7 m) per second. A simple conversion produces a speed of 19.43 miles (31.3 km) per hour, a rate faster than any human can run. If a cheetah is after you-both prey and pray.

Procedure

1) Have students write notes on how the various animals obtain their food: eating plants, pouncing, jumping into the air and chasing.

2) Replay the sequence on the cheetah and ask students what is known about this animal. Have them describe the running pattern of the animal. Introduce the question, "Could you escape from a cheetah if it were chasing you?"

3) Using an Internet search engine, CD-ROM encyclopedia or other materials, find the vital statistics of the cheetah and a picture of the side view of a cheetah.

4) With a ruler, have the students measure the length of the animal from shoulder to shoulder and record the value. Assume the value represents the average length of a cheetah. Next, have the students measure the length of each leg from shoulder to the ground. Use a proportion to determine the length of each limb. These values are combined to find the extended length of the animal.

5) Show the film of the cheetah in slow motion and count the number of times the animal bounds until it turns.

6) Rerun the sequence in real time and have students time the length of the sequence. This should be done with several groups and the results averaged.

7) Calculations

a) By multiplying the number of bounds by the length of the extended animal, the distance the animal traveled can be determined.

b) Dividing the distance traveled by the number of seconds in the run to obtain the distance the animal traveled in one second.

c) Multiplying the distance traveled in one second by 60 will give the distance traveled in one minute.

d) Multiply the distance traveled in one minute by 60 to find the distance the animal would travel in one hour at that rate.

e) Divide the result by 5250 feet/mile (1000 m/km) to determine the number of miles (kilometers) the animal would travel in an hour if it could sustain that speed.

8) Take the students to an area where a known section has been measured. Time each student as they run through the section. Use the distance and time to determine the speed of the child.

9) Have students write paragraphs on:

a) comparing their speed to that of a cheetah

b) what they learned from this activity

c) what errors could have affected the results of this investigation

d) how photographs and slow motion photography can be used to study nature

Cyber ZooMobile http://www.primenet.com/~brendel/cheet.html

Private site with great information and pictures. Describes life cycles and physical characteristics of the cheetah.

Nature: Cheetahs in a Hot Spot http://www.pbs.org/wnet/nature/cheetahs/index.html

This site from the PBS series NATURE describes cheetahs and efforts to preserve them.

The Living Edens: Ngorongoro http://www.pbs.org/edens/ngorongoro/creatures.html

This site from PBS describes cheetahs and their history in Africa.

Assessment Recommendations

Each student should complete a data chart, sheet of calculations and written paragraphs. The calculations should be assessed on accuracy. The paragraphs should be assessed by a rubric you develop that reflects the number of identified points in the content of each paragraph.

1. Students may take their own photographs or films of a dog, cat or other pets and use slow motion to analyze the movements.